1
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Bui HT, Wolf C, Wang Y, Haze M, Ardavan A, Heinrich AJ, Phark SH. All-Electrical Driving and Probing of Dressed States in a Single Spin. ACS Nano 2024; 18:12187-12193. [PMID: 38698541 DOI: 10.1021/acsnano.4c00196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
The subnanometer distance between tip and sample in a scanning tunneling microscope (STM) enables the application of very large electric fields with a strength as high as ∼1 GV/m. This has allowed for efficient electrical driving of Rabi oscillations of a single spin on a surface at a moderate radiofrequency (RF) voltage on the order of tens of millivolts. Here, we demonstrate the creation of dressed states of a single electron spin localized in the STM tunnel junction by using resonant RF driving voltages. The read-out of these dressed states was achieved all electrically by a weakly coupled probe spin. Our work highlights the strength of the atomic-scale geometry inherent to the STM that facilitates the creation and control of dressed states, which are promising for the design of atomic scale quantum devices using individual spins on surfaces.
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Affiliation(s)
- Hong T Bui
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Department of Physics, Ewha Womans University, Seoul 03760, Korea
| | - Christoph Wolf
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Ewha Womans University, Seoul 03760, Korea
| | - Yu Wang
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Ewha Womans University, Seoul 03760, Korea
| | - Masahiro Haze
- The Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
| | - Arzhang Ardavan
- CAESR, Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Andreas J Heinrich
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Department of Physics, Ewha Womans University, Seoul 03760, Korea
| | - Soo-Hyon Phark
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Korea
- Ewha Womans University, Seoul 03760, Korea
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2
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Hinoshita M, Abe T, Sato A, Maeda Y, Takeyoshi M. Modified ESR-based photosafety test (ESR-PT) detecting singlet oxygen and free radical formation. J Appl Toxicol 2024; 44:651-662. [PMID: 38058230 DOI: 10.1002/jat.4569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 11/21/2023] [Accepted: 11/21/2023] [Indexed: 12/08/2023]
Abstract
The electron spin resonance-based photosafety test (ESR-PT) was modified using a new parameter, photoreactivity index (PRI), to detect singlet oxygen and free radical photoproducts simultaneously. With this modification, the modified ESR-PT is expected to reduce the number of false negative results due to chemicals producing free radical photoproducts other than singlet oxygen. The assay performance of the modified ESR-PT was evaluated using 56 chemicals, including hydrophobic chemicals. When using the PRI cutoff value of 2.0 in the modified ESR-PT, the accuracy relative to photosafety reference data was 91.1%, and the applicability (100%) was better than the other non-animal photosafety test. Among the chemicals producing positive results, bithionol, fenticlor, and doxycycline HCl were considered positive based on the detection of free radical photoproducts, suggesting that these three chemicals may have phototoxic or photoallergic potential via radical reactions. Additionally, this finding demonstrated the fundamental advantage of the modified ESR-PT using ESR spectroscopy, which can detect radicals selectively and quantitatively. Accordingly, the new parameter PRI is effective for photosafety evaluations based on not only singlet oxygen but also free radical photoproducts generated from chemicals. Therefore, the modified ESR-PT has a great potential for a photosafety test method applicable to various chemicals.
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Affiliation(s)
- Masumi Hinoshita
- CERI Osaka, Chemicals Evaluation and Research Institute, Osaka, Japan
| | - Takayuki Abe
- CERI Tokyo, Chemicals Evaluation and Research Institute, Tokyo, Japan
| | - Asako Sato
- Chemicals Assessment and Research Center, Chemicals Evaluation and Research Institute, Tokyo, Japan
| | - Yosuke Maeda
- Chemicals Assessment and Research Center, Chemicals Evaluation and Research Institute, Tokyo, Japan
| | - Masahiro Takeyoshi
- Chemicals Assessment and Research Center, Chemicals Evaluation and Research Institute, Tokyo, Japan
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3
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Maffeis V, Skowicki M, Wolf KMP, Chami M, Schoenenberger CA, Vogel V, Palivan CG. Advancing the Design of Artificial Nano-organelles for Targeted Cellular Detoxification of Reactive Oxygen Species. Nano Lett 2024; 24:2698-2704. [PMID: 38408754 PMCID: PMC10921454 DOI: 10.1021/acs.nanolett.3c03888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 02/28/2024]
Abstract
Artificial organelles (AnOs) are in the spotlight as systems to supplement biochemical pathways in cells. While polymersome-based artificial organelles containing enzymes to reduce reactive oxygen species (ROS) are known, applications requiring control of their enzymatic activity and cell-targeting to promote intracellular ROS detoxification are underexplored. Here, we introduce advanced AnOs where the chemical composition of the membrane supports the insertion of pore-forming melittin, enabling molecular exchange between the AnO cavity and the environment, while the encapsulated lactoperoxidase (LPO) maintains its catalytic function. We show that H2O2 outside AnOs penetrates through the melittin pores and is rapidly degraded by the encapsulated enzyme. As surface attachment of cell-penetrating peptides facilitates AnOs uptake by cells, electron spin resonance revealed a remarkable enhancement in intracellular ROS detoxification by these cell-targeted AnOs compared to nontargeted AnOs, thereby opening new avenues for a significant reduction of oxidative stress in cells.
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Affiliation(s)
- Viviana Maffeis
- Department
of Chemistry, University of Basel, Mattenstrasse 22, 4002 Basel, Switzerland
- NCCR-Molecular
Systems Engineering, 4002 Basel, Switzerland
| | - Michal Skowicki
- Department
of Chemistry, University of Basel, Mattenstrasse 22, 4002 Basel, Switzerland
- NCCR-Molecular
Systems Engineering, 4002 Basel, Switzerland
| | - Konstantin M. P. Wolf
- NCCR-Molecular
Systems Engineering, 4002 Basel, Switzerland
- Laboratory
of Applied Mechanobiology, Institute of Translational Medicine, Department
of Health Sciences and Technology, ETH Zurich, 8092 Zurich, Switzerland
| | - Mohamed Chami
- BioEM
lab, Biozentrum, University of Basel, 4056 Basel, Switzerland
| | | | - Viola Vogel
- NCCR-Molecular
Systems Engineering, 4002 Basel, Switzerland
- Laboratory
of Applied Mechanobiology, Institute of Translational Medicine, Department
of Health Sciences and Technology, ETH Zurich, 8092 Zurich, Switzerland
| | - Cornelia G. Palivan
- Department
of Chemistry, University of Basel, Mattenstrasse 22, 4002 Basel, Switzerland
- NCCR-Molecular
Systems Engineering, 4002 Basel, Switzerland
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4
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Gavrilova T, Deeva Y, Uporova A, Chupakhina T, Yatsyk I, Rogov A, Cherosov M, Batulin R, Khrizanforov M, Khantimerov S. Li 3V 2(PO 4) 3 Cathode Material: Synthesis Method, High Lithium Diffusion Coefficient and Magnetic Inhomogeneity. Int J Mol Sci 2024; 25:2884. [PMID: 38474129 DOI: 10.3390/ijms25052884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/25/2024] [Accepted: 02/26/2024] [Indexed: 03/14/2024] Open
Abstract
Li3V2(PO4)3 cathodes for Li-ion batteries (LIBs) were synthesized using a hydrothermal method with the subsequent annealing in an argon atmosphere to achieve optimal properties. The X-ray diffraction analysis confirmed the material's single-phase nature, while the scanning electron microscopy revealed a granular structure, indicating a uniform particle size distribution, beneficial for electrochemical performance. Magnetometry and electron spin resonance studies were conducted to investigate the magnetic properties, confirming the presence of the relatively low concentration and highly uniform distribution of tetravalent vanadium ions (V4+), which indicated low lithium deficiency values in the original structure and a high degree of magnetic homogeneity in the sample, an essential factor for consistent electrochemical behavior. For this pure phase Li3V2(PO4)3 sample, devoid of any impurities such as carbon or salts, extensive electrochemical property testing was performed. These tests resulted in the experimental discovery of a remarkably high lithium diffusion coefficient D = 1.07 × 10-10 cm2/s, indicating excellent ionic conductivity, and demonstrated impressive stability of the material with sustained performance over 1000 charge-discharge cycles. Additionally, relithiated Li3V2(PO4)3 (after multiple electrochemical cycling) samples were investigated using scanning electron microscopy, magnetometry and electron spin resonance methods to determine the extent of degradation. The combination of high lithium diffusion coefficients, a low degradation rate and remarkable cycling stability positions this Li3V2(PO4)3 material as a promising candidate for advanced energy storage applications.
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Affiliation(s)
- Tatiana Gavrilova
- Kazan E. K. Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Sibirsky Tract, 10/7, 420029 Kazan, Russia
| | - Yulia Deeva
- Institute of Solid State Chemistry of the Ural Branch of RAS, Pervomaiskaya Str., 91, 620990 Ekaterinburg, Russia
| | - Anastasiya Uporova
- Institute of Solid State Chemistry of the Ural Branch of RAS, Pervomaiskaya Str., 91, 620990 Ekaterinburg, Russia
| | - Tatiana Chupakhina
- Institute of Solid State Chemistry of the Ural Branch of RAS, Pervomaiskaya Str., 91, 620990 Ekaterinburg, Russia
| | - Ivan Yatsyk
- Kazan E. K. Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Sibirsky Tract, 10/7, 420029 Kazan, Russia
| | - Alexey Rogov
- Kazan E. K. Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Sibirsky Tract, 10/7, 420029 Kazan, Russia
- Institute of Physics, Kazan Federal University, Kremlyovskaya Str., 18, 420008 Kazan, Russia
| | - Mikhail Cherosov
- Institute of Physics, Kazan Federal University, Kremlyovskaya Str., 18, 420008 Kazan, Russia
| | - Ruslan Batulin
- Institute of Physics, Kazan Federal University, Kremlyovskaya Str., 18, 420008 Kazan, Russia
| | - Mikhail Khrizanforov
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Arbuzov Str., 8, 420088 Kazan, Russia
- Aleksander Butlerov Institute of Chemistry, Kazan Federal University, 1/29 Lobachevskogo Str., 420008 Kazan, Russia
| | - Sergey Khantimerov
- Kazan E. K. Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Sibirsky Tract, 10/7, 420029 Kazan, Russia
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Kimata H, Yamaguchi S, Gotanda T, Xue D, Asai H, Shimazaki A, Wakamiya A, Marumoto K. Open-Circuit-Voltage Improvement Mechanism of Perovskite Solar Cells Revealed by Operando Spin Observation. ACS Appl Mater Interfaces 2023; 15:58539-58547. [PMID: 38055892 DOI: 10.1021/acsami.3c16361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Organic-inorganic hybrid perovskite solar cells have attracted much attention as important next-generation solar cells. Their solar cell performance is known to change during operation, but the root cause of the instability remains unclear. This report describes an investigation using electron spin resonance (ESR) to evaluate an improvement mechanism for the open-circuit voltage, VOC, of inverted perovskite solar cells at the initial stage of device operation. The ESR study revealed electron transfer at the interface from the perovskite layer to the hole-transport layer not only under dark conditions but also under light irradiation, where electrons are subsequently trapped in the hole-transport layer. An electron barrier is enhanced at the perovskite/hole-transport-layer interface, improving field-effect passivation at the interface. Thereby, the interface recombination velocity is reduced, and thus the VOC improves. These findings are crucially important for elucidating the mechanisms of device performance changes under operation. They reveal a relation between charge transfer and performance improvement, which is valuable for the further development of efficient perovskite solar cells.
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Affiliation(s)
- Haru Kimata
- Department of Materials Science, Institute of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Seira Yamaguchi
- Department of Materials Science, Institute of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Takeshi Gotanda
- Corporate Research & Development Center, Toshiba Corporation, Kawasaki, Kanagawa 230-0024, Japan
- Toshiba Energy Systems & Solutions Corporation, Kawasaki, Kanagawa 212-8585, Japan
| | - Dong Xue
- Department of Materials Science, Institute of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Haruka Asai
- Department of Materials Science, Institute of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Ai Shimazaki
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Atsushi Wakamiya
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Kazuhiro Marumoto
- Department of Materials Science, Institute of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
- Tsukuba Research Center for Energy Materials Science (TREMS), University of Tsukuba, Ibaraki 305-8571, Japan
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6
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Jones MT, Monir MS, Krauth FN, Macha P, Hsueh YL, Worrall A, Keizer JG, Kranz L, Gorman SK, Chung Y, Rahman R, Simmons MY. Atomic Engineering of Molecular Qubits for High-Speed, High-Fidelity Single Qubit Gates. ACS Nano 2023; 17:22601-22610. [PMID: 37930801 DOI: 10.1021/acsnano.3c06668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
Universal quantum computing requires fast single- and two-qubit gates with individual qubit addressability to minimize decoherence errors during processor operation. Electron spin qubits using individual phosphorus donor atoms in silicon have demonstrated long coherence times with high fidelities, providing an attractive platform for scalable quantum computing. While individual qubit addressability has been demonstrated by controlling the hyperfine interaction between the electron and nuclear wave function in a global magnetic field, the small hyperfine Stark coefficient of 0.34 MHz/MV m-1 achieved to date has limited the speed of single quantum gates to ∼42 μs to avoid rotating neighboring qubits due to power broadening from the antenna. The use of molecular 2P qubits with more than one donor atom has not only demonstrated fast (0.8 ns) two-qubit SWAP gates and long spin relaxation times of ∼30 s but provides an alternate way to achieve high selectivity of the qubit resonance frequency. Here, we show in two different devices that by placing the donors with comparable interatomic spacings (∼0.8 nm) but along different crystallographic axes, either the [110] or [310] orientations using STM lithography, we can engineer the hyperfine Stark shift from 1 MHz/MV m-1 to 11.2 MHz/MV m-1, respectively, a factor of 10 difference. NEMO atomistic calculations show that larger hyperfine Stark coefficients of up to ∼70 MHz/MV m-1 can be achieved within 2P molecules by placing the donors ≥5 nm apart. When combined with Gaussian pulse shaping, we show that fast single qubit gates with 2π rotation times of 10 ns and ∼99% fidelity single qubit operations are feasible without affecting neighboring qubits. By increasing the single qubit gate time to ∼550 ns, two orders of magnitude faster than previously measured, our simulations confirm that >99.99% single qubit control fidelities are achievable.
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Affiliation(s)
- Michael T Jones
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
| | - Md Serajum Monir
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
- School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Felix N Krauth
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
| | - Pascal Macha
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
| | - Yu-Ling Hsueh
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
- School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Angus Worrall
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
- School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Joris G Keizer
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
| | - Ludwik Kranz
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
| | - Samuel K Gorman
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
| | - Yousun Chung
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
| | - Rajib Rahman
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Michelle Y Simmons
- Centre of Excellence for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia
- Silicon Quantum Computing Pty Ltd., Level 2, Newton Building, UNSW Sydney, Kensington, New South Wales 2052, Australia
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7
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Kandarakova I, Yakushkin S, Nesterov N, Philippov A, Martyanov O. Reactivation of Ni-TiO 2 catalysts in hydrogen flow and in supercritical 2-propanol-Comparative study by electron spin resonance in situ. Magn Reson Chem 2023; 61:574-581. [PMID: 37681399 DOI: 10.1002/mrc.5385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 07/10/2023] [Accepted: 07/24/2023] [Indexed: 09/09/2023]
Abstract
Highly dispersed Ni-TiO2 catalyst has been studied in the process of preparation and under catalytic transfer hydrogenation reaction conditions in supercritical 2-propanol (250°C, 70 bar) using electron spin resonance in situ. Electron spin resonance in situ has been used to study the process of the catalyst passivation and subsequent reduction of the oxide layer in the gas flow. Reduction of the NiO layer on the surface of passivated Ni nanoparticles has been detected in supercritical 2-propanol, which is in agreement with kinetic modeling data. It has been found that the reduction of the nickel oxide layer in supercritical 2-propanol occurs at a lower temperature compared with the reduction in hydrogen flow, according to in situ electron spin resonance study.
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Affiliation(s)
- Irina Kandarakova
- Boreskov Institute of Catalysis, Russian Academy of Sciences, Novosibirsk, Russia
| | - Stanislav Yakushkin
- Boreskov Institute of Catalysis, Russian Academy of Sciences, Novosibirsk, Russia
| | - Nikolay Nesterov
- Boreskov Institute of Catalysis, Russian Academy of Sciences, Novosibirsk, Russia
| | - Alexey Philippov
- Boreskov Institute of Catalysis, Russian Academy of Sciences, Novosibirsk, Russia
| | - Oleg Martyanov
- Boreskov Institute of Catalysis, Russian Academy of Sciences, Novosibirsk, Russia
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8
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Andreozzi L, Martinelli E. An Electron Spin Resonance Study Comparing Nanometer-Nanosecond Dynamics in Diblock Copolymers and Their Poly(methyl Methacrylate) Binary Blends. Polymers (Basel) 2023; 15:4195. [PMID: 37896439 PMCID: PMC10611165 DOI: 10.3390/polym15204195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/12/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Block copolymers are a class of materials that are particularly interesting with respect to their capability to self-assemble in ordered structures. In this context, the coupling between environment and dynamics is particularly relevant given that movements at the molecular level influence various properties of macromolecules. Mixing the polymer with a second macromolecule appears to be an easy method for studying these relationships. In this work, we studied blends of poly(methyl methacrylate) (PMMA) and a block copolymer composed of PMMA as the first block and poly(3-methyl-4-[6-(methylacryloyloxy)-hexyloxy]-4'-pentyloxy azobenzene) as the second block. The relaxational properties of these blends were investigated via electron spin resonance (ESR) spectroscopy, which is sensitive to nanometric length scales. The results of the investigations on the blends were related to the dynamic behavior of the copolymers. At the nanoscale, the study revealed the presence of heterogeneities, with slow and fast dynamics available for molecular reorientation, which are further modulated by the ability of the block copolymers to form supramolecular structures. For blends, the heterogeneities at the nanoscale were still detected. However, it was observed that the presence of the PMMA as a major component of the blends modified their dynamic behavior.
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Affiliation(s)
- Laura Andreozzi
- Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3, 56127 Pisa, Italy
- Istituto per i Processi Chimico-Fisici-Consiglio Nazionale delle Ricerche (IPCF-CNR), Via G. Moruzzi 1, 56124 Pisa, Italy
- CISUP, Centro per l’Integrazione della Strumentazione dell’Università di Pisa, Lungarno Pacinotti 43/44, 56126 Pisa, Italy;
| | - Elisa Martinelli
- CISUP, Centro per l’Integrazione della Strumentazione dell’Università di Pisa, Lungarno Pacinotti 43/44, 56126 Pisa, Italy;
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy
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9
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Karpova SG, Olkhov AA, Varyan IA, Shilkina NG, Berlin AA, Popov AA, Iordanskii AL. Biocomposites Based on Electrospun Fibers of Poly(3-hydroxybutyrate) and Nanoplatelets of Graphene Oxide: Thermal Characteristics and Segmental Dynamics at Hydrothermal and Ozonation Impact. Polymers (Basel) 2023; 15:4171. [PMID: 37896415 PMCID: PMC10610569 DOI: 10.3390/polym15204171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/05/2023] [Accepted: 10/08/2023] [Indexed: 10/29/2023] Open
Abstract
In order to create new biodegradable nanocomposites for biomedicine, packaging, and environmentally effective adsorbents, ultra-thin composite fibers consisting of poly(3-hydroxybutyrate) (PHB) and graphene oxide (GO) were obtained by electrospinning. Comprehensive studies of ultrathin fibers combining thermal characteristics, dynamic electron paramagnetic resonance (ESR) probe measurements, and scanning electron microscopy (SEM) were carried out. It is shown that at the addition of 0.05, 0.1, 0.3, and 1% OG, the morphology and geometry of the fibers and their thermal and dynamic characteristics depend on the composite content. The features of the crystalline and amorphous structure of the PHB fibers were investigated by the ESR and DSC methods. For all compositions of PHB/GO, a nonlinear dependence of the correlation time of molecular mobility TEMPO probe (τ) and enthalpy of biopolyether melting (ΔH) is observed. The influence of external factors on the structural-dynamic properties of the composite fiber, such as hydrothermal exposure of samples in aqueous medium at 70 °C and ozonolysis, leads to extreme dependencies of τ and ΔH, which reflect two processes affecting the structure in opposite ways. The plasticizing effect of water leads to thermal destruction of the orientation of the pass-through chains in the amorphous regions of PHB and a subsequent decrease in the crystalline phase, and the aggregation of GO nanoplates into associates, reducing the number of GO-macromolecule contacts, thus increasing segmental mobility, as confirmed by decreasing τ values. The obtained PHB/GO fibrillar composites should find application in the future for the creation of new therapeutic and packaging systems with improved biocompatibility and high-barrier properties.
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Affiliation(s)
- Svetlana G. Karpova
- Department of Biological and Chemical Physics of Polymers, Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 4 Kosygina Street, 119334 Moscow, Russia; (S.G.K.); (A.A.O.); (A.A.P.)
| | - Anatoly A. Olkhov
- Department of Biological and Chemical Physics of Polymers, Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 4 Kosygina Street, 119334 Moscow, Russia; (S.G.K.); (A.A.O.); (A.A.P.)
- Academic Department of Innovational Materials and Technologies Chemistry, Plekhanov Russian University of Economics, 36 Stremyanny Lane, 117997 Moscow, Russia
| | - Ivetta A. Varyan
- Department of Biological and Chemical Physics of Polymers, Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 4 Kosygina Street, 119334 Moscow, Russia; (S.G.K.); (A.A.O.); (A.A.P.)
- Academic Department of Innovational Materials and Technologies Chemistry, Plekhanov Russian University of Economics, 36 Stremyanny Lane, 117997 Moscow, Russia
| | - Natalia G. Shilkina
- N. N. Semenov Federal Research Center for Chemical Physics Academy of Science, 119991 Moscow, Russia; (N.G.S.); (A.A.B.)
| | - Alexander A. Berlin
- N. N. Semenov Federal Research Center for Chemical Physics Academy of Science, 119991 Moscow, Russia; (N.G.S.); (A.A.B.)
| | - Anatoly A. Popov
- Department of Biological and Chemical Physics of Polymers, Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 4 Kosygina Street, 119334 Moscow, Russia; (S.G.K.); (A.A.O.); (A.A.P.)
- Academic Department of Innovational Materials and Technologies Chemistry, Plekhanov Russian University of Economics, 36 Stremyanny Lane, 117997 Moscow, Russia
| | - Alexey L. Iordanskii
- N. N. Semenov Federal Research Center for Chemical Physics Academy of Science, 119991 Moscow, Russia; (N.G.S.); (A.A.B.)
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10
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Zhang X, Reina-Gálvez J, Wolf C, Wang Y, Aubin H, Heinrich AJ, Choi T. Influence of the Magnetic Tip on Heterodimers in Electron Spin Resonance Combined with Scanning Tunneling Microscopy. ACS Nano 2023; 17:16935-16942. [PMID: 37643247 DOI: 10.1021/acsnano.3c04024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Investigating the quantum properties of individual spins adsorbed on surfaces by electron spin resonance combined with scanning tunneling microscopy (ESR-STM) has shown great potential for the development of quantum information technology on the atomic scale. A magnetic tip exhibiting high spin polarization is critical for performing an ESR-STM experiment. While the tip has been conventionally treated as providing a static magnetic field in ESR-STM, it was found that the tip can exhibit bistability, influencing ESR spectra. Ideally, the ESR splitting caused by the magnetic interaction between two spins on a surface should be independent of the tip. However, we found that the measured ESR splitting of a metal atom-molecule heterodimer can be tip-dependent. Detailed theoretical analysis reveals that this tip-dependent ESR splitting is caused by a different interaction energy between the tip and each spin of the heterodimer. Our work provides a comprehensive reference for characterizing tip features in ESR-STM experiments and highlights the importance of employing a proper physical model when describing the ESR tip, in particular, for heterospin systems.
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Affiliation(s)
- Xue Zhang
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Republic of Korea
- Ewha Womans University, Seoul 03760, Republic of Korea
- Spin-X Institute, School of Microelectronics, South China University of Technology, Guangzhou 511442, People's Republic of China
| | - Jose Reina-Gálvez
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Republic of Korea
- Ewha Womans University, Seoul 03760, Republic of Korea
| | - Christoph Wolf
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Republic of Korea
- Ewha Womans University, Seoul 03760, Republic of Korea
| | - Yu Wang
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Republic of Korea
- Ewha Womans University, Seoul 03760, Republic of Korea
| | - Hervé Aubin
- Universités Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120 Palaiseau, France
| | - Andreas J Heinrich
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Republic of Korea
- Department of Physics, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Taeyoung Choi
- Department of Physics, Ewha Womans University, Seoul 03760, Republic of Korea
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11
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Phark S, Bui HT, Ferrón A, Fernández‐Rossier J, Reina‐Gálvez J, Wolf C, Wang Y, Yang K, Heinrich AJ, Lutz CP. Electric-Field-Driven Spin Resonance by On-Surface Exchange Coupling to a Single-Atom Magnet. Adv Sci (Weinh) 2023; 10:e2302033. [PMID: 37466177 PMCID: PMC10520627 DOI: 10.1002/advs.202302033] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/11/2023] [Indexed: 07/20/2023]
Abstract
Coherent control of individual atomic and molecular spins on surfaces has recently been demonstrated by using electron spin resonance (ESR) in a scanning tunneling microscope (STM). Here, a combined experimental and modeling study of the ESR of a single hydrogenated Ti atom that is exchange-coupled to a Fe adatom positioned 0.6-0.8 nm away by means of atom manipulation is presented. Continuous wave and pulsed ESR of the Ti spin show a Rabi rate with two contributions, one from the tip and the other from the Fe, whose spin interactions with Ti are modulated by the radio-frequency electric field. The Fe contribution is comparable to the tip, as revealed by its dominance when the tip is retracted, and tunable using a vector magnetic field. The new ESR scheme allows on-surface individual spins to be addressed and coherently controlled without the need for magnetic interaction with a tip. This study establishes a feasible implementation of spin-based multi-qubit systems on surfaces.
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Affiliation(s)
- Soo‐hyon Phark
- Center for Quantum NanoscienceInstitute for Basic Science (IBS)Seoul03760Republic of Korea
- Department of PhysicsEwha Womans UniversitySeoul03760Republic of Korea
- IBM Research DivisionAlmaden Research CenterSan JoseCA95120USA
| | - Hong Thi Bui
- Center for Quantum NanoscienceInstitute for Basic Science (IBS)Seoul03760Republic of Korea
- Department of PhysicsEwha Womans UniversitySeoul03760Republic of Korea
| | - Alejandro Ferrón
- Instituto de Modelado e Innovación Tecnológica (CONICET‐UNNE) and Facultad de Ciencias ExactasNaturales y AgrimensuraUniversidad Nacional del NordesteAvenida Libertad 5400CorrientesW3404AASArgentina
| | | | - Jose Reina‐Gálvez
- Center for Quantum NanoscienceInstitute for Basic Science (IBS)Seoul03760Republic of Korea
- Department of PhysicsEwha Womans UniversitySeoul03760Republic of Korea
| | - Christoph Wolf
- Center for Quantum NanoscienceInstitute for Basic Science (IBS)Seoul03760Republic of Korea
- Department of PhysicsEwha Womans UniversitySeoul03760Republic of Korea
| | - Yu Wang
- Center for Quantum NanoscienceInstitute for Basic Science (IBS)Seoul03760Republic of Korea
- Department of PhysicsEwha Womans UniversitySeoul03760Republic of Korea
| | - Kai Yang
- IBM Research DivisionAlmaden Research CenterSan JoseCA95120USA
- Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing100864China
| | - Andreas J. Heinrich
- Center for Quantum NanoscienceInstitute for Basic Science (IBS)Seoul03760Republic of Korea
- Department of PhysicsEwha Womans UniversitySeoul03760Republic of Korea
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12
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Inoue G, Ohtaki Y, Satoh K, Odanaka Y, Katoh A, Suzuki K, Tomita Y, Eiraku M, Kikuchi K, Harano K, Yagi M, Uchida N, Dohi K. Sedation Therapy in Intensive Care Units: Harnessing the Power of Antioxidants to Combat Oxidative Stress. Biomedicines 2023; 11:2129. [PMID: 37626626 PMCID: PMC10452444 DOI: 10.3390/biomedicines11082129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/20/2023] [Accepted: 07/24/2023] [Indexed: 08/27/2023] Open
Abstract
In critically ill patients requiring intensive care, increased oxidative stress plays an important role in pathogenesis. Sedatives are widely used for sedation in many of these patients. Some sedatives are known antioxidants. However, no studies have evaluated the direct scavenging activity of various sedative agents on different free radicals. This study aimed to determine whether common sedatives (propofol, thiopental, and dexmedetomidine (DEX)) have direct free radical scavenging activity against various free radicals using in vitro electron spin resonance. Superoxide, hydroxyl radical, singlet oxygen, and nitric oxide (NO) direct scavenging activities were measured. All sedatives scavenged different types of free radicals. DEX, a new sedative, also scavenged hydroxyl radicals. Thiopental scavenged all types of free radicals, including NO, whereas propofol did not scavenge superoxide radicals. In this retrospective analysis, we observed changes in oxidative antioxidant markers following the administration of thiopental in patients with severe head trauma. We identified the direct radical-scavenging activity of various sedatives used in clinical settings. Furthermore, we reported a representative case of traumatic brain injury wherein thiopental administration dramatically affected oxidative-stress-related biomarkers. This study suggests that, in the future, sedatives containing thiopental may be redeveloped as an antioxidant therapy through further clinical research.
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Affiliation(s)
- Gen Inoue
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Yuhei Ohtaki
- Department of Emergency Medicine, School of Medicine, The Jikei University, 3-25-8 Nishishinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Kazue Satoh
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Yuki Odanaka
- Center for Instrumental Analysis, School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Akihito Katoh
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Keisuke Suzuki
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Yoshitake Tomita
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Manabu Eiraku
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Kazuki Kikuchi
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Kouhei Harano
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Masaharu Yagi
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
| | - Naoki Uchida
- Clinical Research Institute for Clinical Pharmacology and Therapeutics, Showa University Karasuyama Hospital, 6-11-11 Kitakarasuyama, Setagaya-ku, Tokyo 157-8577, Japan
| | - Kenji Dohi
- Department of Emergency, Disaster and Critical Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; (G.I.)
- Department of Emergency Medicine, School of Medicine, The Jikei University, 3-25-8 Nishishinbashi, Minato-ku, Tokyo 105-8461, Japan
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13
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Sichelschmidt J, Häußler E, Vinokurova E, Baenitz M, Doert T. Electron spin resonance study on the 4 fhoneycomb quantum magnet YbCl 3. J Phys Condens Matter 2023; 35. [PMID: 37459864 DOI: 10.1088/1361-648x/ace815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 07/17/2023] [Indexed: 07/26/2023]
Abstract
The local magnetic properties of Yb3+in the layered honeycomb material YbCl3were investigated by electron spin resonance on single crystals. For in-plane and out-of-plane field orientations theg-factor shows a clear anisotropy (g∥=2.97(8)andg⊥=1.53(4)), whereas the low temperature exchange coupling and the spin relaxation display a rather isotropic character. At elevated temperatures the contribution of the first excited crystal field level (21±2meV) dominates the spin relaxation.
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Affiliation(s)
| | - Ellen Häußler
- TU Dresden, Department of Chemistry and Food Chemistry, Dresden, Germany
| | - Ekaterina Vinokurova
- TU Dresden, Institut für Festkörper- und Materialphysik, 01062 Dresden, Germany
- Leibniz IFW Dresden, Institute of Solid State Research, 01069 Dresden, Germany
| | - M Baenitz
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - Thomas Doert
- TU Dresden, Department of Chemistry and Food Chemistry, Dresden, Germany
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14
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Kurokawa H, Marella TK, Matsui H, Kuroki Y, Watanabe MM. Therapeutic Potential of Seaweed-Derived Laminaran: Attenuation of Clinical Drug Cytotoxicity and Reactive Oxygen Species Scavenging. Antioxidants (Basel) 2023; 12:1328. [PMID: 37507868 PMCID: PMC10376328 DOI: 10.3390/antiox12071328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/20/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
β-glucan has been shown to be effective for several diseases such as immune regulation and blood pressure suppression. Seaweed contains a β-1,3/1,6-glucan called laminaran. The present commercial source of β-glucan is black yeast; however, a fermentation process using organic carbon substrates makes production unsustainable, whereas macroalgae provide a sustainable alternative with the use of CO2 and seawater as growth substrates. However, bioactivity studies on laminaran are limited. We aimed to evaluate whether laminaran can scavenge reactive oxygen species (ROS) and attenuate cytotoxicity caused by clinical drugs such as indomethacin (Ind) and dabigatran (Dab). Electron spin resonance assay revealed that laminaran scavenged singlet oxygen (1O2) and superoxide anions (O2•-) directly but did not scavenge hydroxyl radicals (•OH). Mitochondrial ROS detection dye showed that laminaran scavenged mitochondrial O2•- produced upon administration of Ind or Dab. Moreover, significant reductions in •OH and peroxynitrate (ONOO-) levels were observed. Since •OH and ONOO- are generated from O2•- in the cells, laminaran could indirectly suppress the generation of •OH and ONOO- via the removal of O2•-. Both Ind and Dab induce cell injury via ROS production. Laminaran attenuated the cytotoxicity derived from these drugs and may represent a functional food with anti-aging and disease prevention properties.
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Affiliation(s)
- Hiromi Kurokawa
- Algae Biomass Energy System R&D Center, University of Tsukuba, Tennodai 1-1-1, Tsukuba 3058572, Japan
- Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba 3058575, Japan
| | - Thomas Kiran Marella
- Algae Biomass Energy System R&D Center, University of Tsukuba, Tennodai 1-1-1, Tsukuba 3058572, Japan
- Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba 3058575, Japan
| | - Hirofumi Matsui
- Algae Biomass Energy System R&D Center, University of Tsukuba, Tennodai 1-1-1, Tsukuba 3058572, Japan
- Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba 3058575, Japan
| | - Yutaka Kuroki
- Delightex Pte. Ltd., 230 Victoria Street, #15-01 Bugis, Junction Towers, Singapore 188024, Singapore
| | - Makoto M Watanabe
- Algae Biomass Energy System R&D Center, University of Tsukuba, Tennodai 1-1-1, Tsukuba 3058572, Japan
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15
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Zong Y, Chen L, Zeng Y, Xu J, Zhang H, Zhang X, Liu W, Wu D. Do We Appropriately Detect and Understand Singlet Oxygen Possibly Generated in Advanced Oxidation Processes by Electron Paramagnetic Resonance Spectroscopy? Environ Sci Technol 2023. [PMID: 37311080 DOI: 10.1021/acs.est.3c01553] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Electron paramagnetic resonance (EPR) spectroscopy using sterically hindered amine is extensively applied to detect singlet oxygen (1O2) possibly generated in advanced oxidation processes. However, EPR-detectable 1O2 signals were observed in not only the 1O2-dominated hydrogen peroxide (H2O2)/hypochlorite (NaClO) reaction but surprisingly also the 1O2-absent Fe(II)/H2O2, UV/H2O2, and ferrate [Fe(VI)] process with even stronger intensities. By taking advantage of the characteristic reaction between 1O2 and 9,10-diphenyl-anthracene and near-infrared phosphorescent emission of 1O2, 1O2 was excluded in the Fe(II)/H2O2, UV/H2O2, and Fe(VI) process. The false detection of 1O2 was ascribed to the direct oxidation of hindered amine to piperidyl radical by reactive species [e.g., •OH and Fe(VI)/Fe(V)/Fe(IV)] via hydrogen transfer, followed by molecular oxygen addition (forming a piperidylperoxyl radical) and back reaction with piperidyl radical to generate a nitroxide radical, as evidenced by the successful identification of a piperidyl radical intermediate at 100 K and theoretical calculations. Moreover, compared to the highly oxidative species (e.g., •OH and high-valence Fe), the much lower reactivity of 1O2 and the profound nonradiative relaxation of 1O2 in H2O resulted it too selective and inefficient in organic contaminant destruction. This study demonstrated that EPR-based 1O2 detection could be remarkably misled by common oxidative species and thereby jeopardize the understandings on 1O2.
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Affiliation(s)
- Yang Zong
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Long Chen
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yunqiao Zeng
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
| | - Jun Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
| | - Hua Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
| | - Xiaomeng Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
| | - Wen Liu
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
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16
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Haghighirad AA, Klug MT, Duffy L, Liu J, Ardavan A, van der Laan G, Hesjedal T, Snaith HJ. Probing the Local Electronic Structure in Metal Halide Perovskites through Cobalt Substitution. Small Methods 2023; 7:e2300095. [PMID: 36908028 DOI: 10.1002/smtd.202300095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/14/2023] [Indexed: 06/09/2023]
Abstract
Owing to the unique chemical and electronic properties arising from 3d-electrons, substitution with transition metal ions is one of the key routes for engineering new functionalities into materials. While this approach has been used extensively in complex metal oxide perovskites, metal halide perovskites have largely resisted facile isovalent substitution. In this work, it is demonstrated that the substitution of Co2+ into the lattice of methylammonium lead triiodide imparts magnetic behavior to the material while maintaining photovoltaic performance at low concentrations. In addition to comprehensively characterizing its magnetic properties, the Co2+ ions themselves are utilized as probes to sense the local electronic environment of Pb in the perovskite, thereby revealing the nature of their incorporation into the material. A comprehensive understanding of the effect of transition metal incorporation is provided, thereby opening the substitution gateway for developing novel functional perovskite materials and devices for future technologies.
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Affiliation(s)
- Amir A Haghighirad
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford, OX1 3PU, UK
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021, Karlsruhe, Germany
| | - Matthew T Klug
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford, OX1 3PU, UK
| | - Liam Duffy
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford, OX1 3PU, UK
| | - Junjie Liu
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford, OX1 3PU, UK
| | - Arzhang Ardavan
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford, OX1 3PU, UK
| | - Gerrit van der Laan
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE, UK
| | - Thorsten Hesjedal
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford, OX1 3PU, UK
| | - Henry J Snaith
- Department of Physics, University of Oxford, Clarendon Laboratory, Oxford, OX1 3PU, UK
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17
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Ng W, Xu X, Attwood M, Wu H, Meng Z, Chen X, Oxborrow M. Move Aside Pentacene: Diazapentacene-Doped para-Terphenyl, a Zero-Field Room-Temperature Maser with Strong Coupling for Cavity Quantum Electrodynamics. Adv Mater 2023; 35:e2300441. [PMID: 36919948 DOI: 10.1002/adma.202300441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 03/04/2023] [Indexed: 06/02/2023]
Abstract
Masers can deliver ultralow-noise amplification of microwave signals in medical imaging and deep-space communication, with recent research being rekindled through the discovery of gain media operating at room-temperature, eschewing bulky cryogenics that hindered their use. This work shows the discovery of 6,13-diazapentacene doped in para-terphenyl (DAP:PTP) as a maser gain medium that can operate at room-temperature, without an external magnetic field. With a maser output power of -10 dBm, it is on par with pentacene-doped para-terphenyl in masing power, while possessing compelling advantages such as faster amplification startup times, being pumped by longer wavelength light at 620 nm and greater chemical stability from nitrogen groups. Furthermore, the maser bursts from DAP:PTP allow one to reach the strong coupling regime for cavity quantum electrodynamics, with a high cooperativity of 182. The optical and microwave spin dynamics of DAP:PTP are studied in order to evaluate its capabilities as a maser gain medium, where it features fast intersystem crossing and an advantageously higher triplet quantum yield. The results pave the way for the future discovery of similar maser materials and help designate them as promising candidates for quantum sensors, optoelectronic devices and the study of cavity quantum electrodynamic effects at room-temperature.
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Affiliation(s)
- Wern Ng
- Department of Materials, Imperial College London, London, SW7 2AZ, UK
| | - Xiaotian Xu
- Department of Materials, Imperial College London, London, SW7 2AZ, UK
| | - Max Attwood
- Department of Materials, Imperial College London, London, SW7 2AZ, UK
| | - Hao Wu
- Center for Quantum Technology Research and Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Zhu Meng
- Department of Chemistry and Centre for Processible Electronics, Imperial College London, London, W12 0BZ, UK
| | - Xi Chen
- Department of Materials, Imperial College London, London, SW7 2AZ, UK
- Department of Computer Science, University of Southern California, Los Angeles, CA, USA
| | - Mark Oxborrow
- Department of Materials, Imperial College London, London, SW7 2AZ, UK
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Takeda K, Kimura H, Faudree MC, Uchida HT, Sagawa K, Miura E, Salvia M, Nishi Y. A New Strengthening Process for Carbon-Fiber-Reinforced Thermoplastic Polyphenylene Sulfide (CFRTP-PPS) Interlayered Composite by Electron Beam Irradiation to PPS Prior to Lamination Assembly and Hot Press. Materials (Basel) 2023; 16:2823. [PMID: 37049117 PMCID: PMC10095844 DOI: 10.3390/ma16072823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/18/2023] [Accepted: 03/30/2023] [Indexed: 06/19/2023]
Abstract
Impact by hailstone, volcanic rock, bird strike, or also dropping tools can cause damage to aircraft materials. For maximum safety, the goal is to increase Charpy impact strength (auc) of a carbon-fiber-reinforced thermoplastic polyphenylene sulfide polymer (CFRTP-PPS) composite for potential application to commercial aircraft parts. The layup was three cross-weave CF plies alternating between four PPS plies, [PPS-CF-PPS-CF-PPS-CF-PPS], designated [PPS]4[CF]3. To strengthen, a new process for CFRP-PPS was employed applying homogeneous low voltage electron beam irradiation (HLEBI) to both sides of PPS plies prior to lamination assembly with untreated CF, followed by hot press under 4.0 MPa at 573 K for 8 min. Experimental results showed a 5 kGy HLEBI dose was at or near optimum, increasing auc at each accumulative probability, Pf. Optical microscopy of 5 kGy sample showed a reduction in main crack width with significantly reduced CF separation and pull-out; while, scanning electron microscopy (SEM) and electron dispersive X-ray (EDS) mapping showed PPS adhering to CF. Electron spin resonance (ESR) of a 5 kGy sample indicated lengthening of PPS chains as evidenced by a reduction in dangling bond peak. It Is assumed that 5 kGy HLEBI creates strong bonds at the interface while strengthening the PPS bulk. A model is proposed to illustrate the possible strengthening mechanism.
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Affiliation(s)
- Keisuke Takeda
- Graduate School of Engineering, Tokai University, Hiratsuka 259-1292, Japan
| | - Hideki Kimura
- Graduate School of Engineering, Tokai University, Hiratsuka 259-1292, Japan
- Graduate School of Science & Technology, Tokai University, Hiratsuka 259-1292, Japan
| | - Michael C. Faudree
- Graduate School of Engineering, Tokai University, Hiratsuka 259-1292, Japan
- Graduate School of Science & Technology, Tokai University, Hiratsuka 259-1292, Japan
- Faculty of Liberal Arts and Science, Tokyo City University, Yokohama 224-8551, Japan
| | | | - Kohei Sagawa
- Graduate School of Engineering, Tokai University, Hiratsuka 259-1292, Japan
| | - Eiichi Miura
- Graduate School of Engineering, Tokai University, Hiratsuka 259-1292, Japan
- Kanagawa Institute of Industrial Science and Technology (KISTEC), Ebina 243-0435, Japan
| | - Michelle Salvia
- Laboratory of Tribology and Dynamics of Systems (LTDS), Ecole Centrale de Lyon, 69134 Ecully, CEDEX, France
| | - Yoshitake Nishi
- Graduate School of Engineering, Tokai University, Hiratsuka 259-1292, Japan
- Graduate School of Science & Technology, Tokai University, Hiratsuka 259-1292, Japan
- Kanagawa Institute of Industrial Science and Technology (KISTEC), Ebina 243-0435, Japan
- Laboratory of Tribology and Dynamics of Systems (LTDS), Ecole Centrale de Lyon, 69134 Ecully, CEDEX, France
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19
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Boucher MC, Isaac CE, Sun P, Borbat PP, Marohn JA. A Non-Perturbative, Low-Noise Surface Coating for Sensitive Force-Gradient Detection of Electron Spin Resonance in Thin Films. ACS Nano 2023; 17:10.1021/acsnano.2c08635. [PMID: 36625878 PMCID: PMC10330945 DOI: 10.1021/acsnano.2c08635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The sensitivity of magnetic resonance force microscopy (MRFM) is limited by surface noise. Coating a thin-film polymer sample with metal has been shown to decrease, by orders of magnitude, sample-related force noise and frequency noise in MRFM experiments. Using both MRFM and inductively detected measurements of electron-spin resonance, we show that thermally evaporating a 12 nm gold layer on a 40 nm nitroxide-doped polystyrene film inactivates the nitroxide spin labels to a depth of 20 nm, making single-spin measurements difficult or impossible. We introduce a "laminated sample" protocol in which the gold layer is first evaporated on a sacrificial polymer. The sample is deposited on the room-temperature gold layer, removed using solvent lift-off, and placed manually on a coplanar waveguide. Electron spin resonance (ESR) of such a laminated sample was detected via MRFM at cryogenic temperatures using a high-compliance cantilever with an integrated 100-nm-scale cobalt tip. A 20-fold increase of spin signal was observed relative to a thin-film sample prepared instead with an evaporated metal coating. The observed signal is still somewhat smaller than expected, and we discuss possible remaining sources of signal loss.
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Affiliation(s)
- Michael C Boucher
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14853, United States
| | - Corinne E Isaac
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14853, United States
| | - Peter Sun
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14853, United States
| | - Peter P Borbat
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14853, United States
| | - John A Marohn
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14853, United States
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20
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Maltar-Strmečki N, Bortolin E, Kenzhina L, Patrono C, Testa A. Editorial: Developing novel materials and new techniques of biological and physical retrospective dosimetry for affected individuals in radiological and nuclear emergencies. Front Public Health 2023; 10:1117269. [PMID: 36684958 PMCID: PMC9850211 DOI: 10.3389/fpubh.2022.1117269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 12/22/2022] [Indexed: 01/07/2023] Open
Affiliation(s)
- Nadica Maltar-Strmečki
- Laboratory for Electron Spin Resonance, Division of Physical Chemistry, Ruđer Bošković Institute (RBI), Zagreb, Croatia,*Correspondence: Nadica Maltar-Strmečki ✉
| | | | - Laura Kenzhina
- Institute of Radiation Safety and Ecology (IRSE), National Nuclear Center of Kazakhstan, Kurchatov, Kazakhstan
| | - Clarice Patrono
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Rome, Italy
| | - Antonella Testa
- Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Rome, Italy
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21
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Münz F, Wolfschmitt EM, Zink F, Abele N, Hogg M, Hoffmann A, Gröger M, Calzia E, Waller C, Radermacher P, Merz T. Porcine blood cell and brain tissue energy metabolism: Effects of "early life stress". Front Mol Biosci 2023; 10:1113570. [PMID: 37138659 PMCID: PMC10150084 DOI: 10.3389/fmolb.2023.1113570] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 03/31/2023] [Indexed: 05/05/2023] Open
Abstract
Background: Early Life Stress (ELS) may exert long-lasting biological effects, e.g., on PBMC energy metabolism and mitochondrial respiration. Data on its effect on brain tissue mitochondrial respiration is scarce, and it is unclear whether blood cell mitochondrial activity mirrors that of brain tissue. This study investigated blood immune cell and brain tissue mitochondrial respiratory activity in a porcine ELS model. Methods: This prospective randomized, controlled, animal investigation comprised 12 German Large White swine of either sex, which were weaned at PND (postnatal day) 28-35 (control) or PND21 (ELS). At 20-24 weeks, animals were anesthetized, mechanically ventilated and surgically instrumented. We determined serum hormone, cytokine, and "brain injury marker" levels, superoxide anion (O2 •¯) formation and mitochondrial respiration in isolated immune cells and immediate post mortem frontal cortex brain tissue. Results: ELS animals presented with higher glucose levels, lower mean arterial pressure. Most determined serum factors did not differ. In male controls, TNFα and IL-10 levels were both higher than in female controls as well as, no matter the gender in ELS animals. MAP-2, GFAP, and NSE were also higher in male controls than in the other three groups. Neither PBMC routine respiration and brain tissue oxidative phosphorylation nor maximal electron transfer capacity in the uncoupled state (ETC) showed any difference between ELS and controls. There was no significant relation between brain tissue and PBMC, ETC, or brain tissue, ETC, and PBMC bioenergetic health index. Whole blood O2 •¯ concentrations and PBMC O2 •¯ production were comparable between groups. However, granulocyte O2 •¯ production after stimulation with E. coli was lower in the ELS group, and this effect was sex-specific: increased O2 •¯ production increased upon stimulation in all control animals, which was abolished in the female ELS swine. Conclusion: This study provides evidence that ELS i) may, gender-specifically, affect the immune response to general anesthesia as well as O2 •¯ radical production at sexual maturity, ii) has limited effects on brain and peripheral blood immune cell mitochondrial respiratory activity, and iii) mitochondrial respiratory activity of peripheral blood immune cells and brain tissue do not correlate.
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Affiliation(s)
- Franziska Münz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
- Clinic for Anesthesiology and Intensive Care, Ulm University Medical Center, Ulm, Germany
| | - Eva-Maria Wolfschmitt
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Fabian Zink
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Nadja Abele
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Melanie Hogg
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Andrea Hoffmann
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Michael Gröger
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Enrico Calzia
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Christiane Waller
- Department of Psychosomatic Medicine and Psychotherapy, Nuremberg General Hospital, Paracelsus Medical University, Nuremberg, Germany
| | - Peter Radermacher
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
| | - Tamara Merz
- Institute for Anesthesiological Pathophysiology and Process Engineering, Ulm University Medical Center, Ulm, Germany
- Clinic for Anesthesiology and Intensive Care, Ulm University Medical Center, Ulm, Germany
- *Correspondence: Tamara Merz,
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22
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Dayan N, Artzi Y, Jbara M, Cristea D, Blank A. Pulsed Electron-Nuclear Double Resonance in the Fourier Regime. Chemphyschem 2022; 24:e202200624. [PMID: 36464644 DOI: 10.1002/cphc.202200624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 11/24/2022] [Accepted: 12/01/2022] [Indexed: 12/11/2022]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy provides atomic-level molecular structural information. However, in molecules containing unpaired electron spins, NMR signals are difficult to measure directly. In such cases, data is obtained using the electron-nuclear double resonance (ENDOR) method, where nuclei are detected through their interaction with nearby unpaired electron spins. Unfortunately, electron spins spread the ENDOR signals, which challenges current acquisition techniques, often resulting in low spectral resolution that provides limited structural details. Here, we show that by using miniature microwave resonators to detect a small number of electron spins, integrated with miniature NMR coils, one can excite and detect a wide bandwidth of ENDOR data in a single pulse. This facilitates the measurement of ENDOR spectra with narrow lines spread over a large frequency range at much better spectral resolution than conventional approaches, which helps reveal details of the paramagnetic molecules' chemical structure that were not accessible before.
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Affiliation(s)
- Nir Dayan
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, 3200003, Haifa, Israel
| | - Yaron Artzi
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, 3200003, Haifa, Israel
| | - Moamen Jbara
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, 3200003, Haifa, Israel
| | - David Cristea
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, 3200003, Haifa, Israel
| | - Aharon Blank
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, 3200003, Haifa, Israel
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23
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Vasiliev VP, Kabachkov EN, Kulikov AV, Manzhos RA, Morozov IG, Shulga YM. Unexpected Room Temperature Ferromagnetism of a Ball-Milled Graphene Oxide-Melamine Mixture. Molecules 2022; 27:molecules27227698. [PMID: 36431798 PMCID: PMC9692776 DOI: 10.3390/molecules27227698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/15/2022] [Accepted: 11/06/2022] [Indexed: 11/11/2022]
Abstract
Nitrogen-doped carbon nanomaterial (NDCNM) was synthesized by grinding a mixture of graphene oxide and melamine in a planetary mill with both balls and milling chamber of zirconium dioxide. In the electron spin resonance spectrum of NDCNM, a broad signal with g = 2.08 was observed in addition to a narrow signal at g = 2.0034. In the study using a vibrating-sample magnetometer, the synthesized material is presumably a ferromagnet with a coercive force of 100 Oe. The specific magnetization at 10,000 Oe is approximately 0.020 and 0.055 emu/g at room temperature and liquid nitrogen temperature, respectively.
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Affiliation(s)
- Vladimir P. Vasiliev
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry of RAS, Acad. Semenov Ave., 1, 142432 Chernogolovka, Russia
| | - Eugene N. Kabachkov
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry of RAS, Acad. Semenov Ave., 1, 142432 Chernogolovka, Russia
| | - Alexander V. Kulikov
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry of RAS, Acad. Semenov Ave., 1, 142432 Chernogolovka, Russia
| | - Roman A. Manzhos
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry of RAS, Acad. Semenov Ave., 1, 142432 Chernogolovka, Russia
| | - Iurii G. Morozov
- Merzhanov Institute of Structural Macrokinetics and Materials Science of RAS, Acad. Osipyan St., 8, 142432 Chernogolovka, Russia
| | - Yury M. Shulga
- Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry of RAS, Acad. Semenov Ave., 1, 142432 Chernogolovka, Russia
- Department of Functional Polymer Materials, National University of Science and Technology MISIS, Leninsky Ave., 4, 119049 Moscow, Russia
- Correspondence:
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24
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Farinacci L, Veldman LM, Willke P, Otte S. Experimental Determination of a Single Atom Ground State Orbital through Hyperfine Anisotropy. Nano Lett 2022; 22:8470-8474. [PMID: 36305860 PMCID: PMC9650725 DOI: 10.1021/acs.nanolett.2c02783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 10/25/2022] [Indexed: 06/16/2023]
Abstract
Historically, electron spin resonance (ESR) has provided excellent insight into the electronic, magnetic, and chemical structure of samples hosting spin centers. In particular, the hyperfine interaction between the electron and the nuclear spins yields valuable structural information about these centers. In recent years, the combination of ESR and scanning tunneling microscopy (ESR-STM) has allowed to acquire such information about individual spin centers of magnetic atoms bound atop a surface, while additionally providing spatial information about the binding site. Here, we conduct a full angle-dependent investigation of the hyperfine splitting for individual hydrogenated titanium atoms on MgO/Ag(001) by measurements in a vector magnetic field. We observe strong anisotropy in both the g factor and the hyperfine tensor. Combining the results of the hyperfine splitting with the symmetry properties of the binding site obtained from STM images and a basic point charge model allows us to predict the shape of the electronic ground state configuration of the titanium atom. Relying on experimental values only, this method paves the way for a new protocol for electronic structure analysis for spin centers on surfaces.
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Affiliation(s)
- Laëtitia Farinacci
- Department
of Quantum Nanoscience, Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJDelft, The Netherlands
| | - Lukas M. Veldman
- Department
of Quantum Nanoscience, Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJDelft, The Netherlands
| | - Philip Willke
- Physikalisches
Institut, Karlsruhe Institute of Technology, 76131Karlsruhe, Germany
| | - Sander Otte
- Department
of Quantum Nanoscience, Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJDelft, The Netherlands
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25
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Penkman KEH, Duller GAT, Roberts HM, Colarossi D, Dickinson MR, White D. Dating the Paleolithic: Trapped charge methods and amino acid geochronology. Proc Natl Acad Sci U S A 2022; 119:e2109324119. [PMID: 36252044 DOI: 10.1073/pnas.2109324119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Despite the vast array of different geochronological tools available, dating the Paleolithic remains one of the discipline’s greatest challenges. This review focuses on two different dating approaches: trapped charge and amino acid geochronology. While differing in their fundamental principles, both exploit time-dependent changes in signals found within crystals to generate a chronology for the material dated and hence, the associated deposits. Within each method, there is a diverse range of signals that can be analyzed, each covering different time ranges, applicable to different materials and suitable for different paleoenvironmental and archaeological contexts. This multiplicity of signals can at first sight appear confusing, but it is a fundamental strength of the techniques, allowing internal checks for consistency and providing more information than simply a chronology. For each technique, we present an overview of the basis for the time-dependent signals and the types of material that can be analyzed, with examples of their archaeological application, as well as their future potential.
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26
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Gao HX, Chen N, He Q, Shi B, Yu ZL, Zeng WC. Effects of Ligustrum robustum (Rxob.) Blume extract on the quality of peanut and palm oils during storage and frying process. J Food Sci 2022; 87:4504-4521. [PMID: 36124403 DOI: 10.1111/1750-3841.16311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/27/2022] [Accepted: 08/08/2022] [Indexed: 11/26/2022]
Abstract
The potential uses of Ligustrum robustum (Rxob.) Blume extract as a natural antioxidant to protect the quality of different oils during storage and frying process were studied. The results showed that L. robustum extract has been shown to retard the decline in the quality of both oils based on the tests of acid value, peroxide value, p-anisidine value, color, volatile flavor, and fatty acid compositions, and the protective effect of L. robustum extract on the quality of peanut oil was better than that of palm oil. By the component analysis, L. robustum extract was found to have a total phenols content of 140.75 ± 1.52 mg/g, and ligurobustoside C was identified as the main phenolic compound. The thermogravimetric and differential scanning calorimetry results showed that L. robustum extract enhanced the oxidative stability of peanut and palm oils. In addition, Fourier transform infrared results indicated that L. robustum extract had protective effects on the C=C bond and ester bond of oil molecule. Moreover, by using electron spin resonance technique, L. robustum extract showed the ability to inhibit and scavenge alkyl-free radicals in both oils. The present results suggested that L. robustum extract may protect the quality of oils during the storage and frying process by inhibiting the oxidation of unsaturated fatty acids and might be a potential natural antioxidant in the food industry. PRACTICAL APPLICATIONS: The excellent antioxidant ability of Ligustrum robustum (Rxob.) Blume extract on the oxidation of different oils and its low price indicated that it could be used as a new low-cost natural antioxidant in oil processing.
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Affiliation(s)
- Hao-Xiang Gao
- Antioxidant Polyphenols Team, Department of Food Engineering, Sichuan University, Chengdu, PR China
| | - Nan Chen
- Antioxidant Polyphenols Team, Department of Food Engineering, Sichuan University, Chengdu, PR China
| | - Qiang He
- The Key Laboratory of Food Science and Technology of Sichuan Province of Education, Sichuan University, Chengdu, PR China
| | - Bi Shi
- Department of Biomass and Leather Engineering, Sichuan University, Chengdu, PR China
| | - Zhi-Long Yu
- Department of Food Science and Agricultural Chemistry, Faculty of Agricultural and Environmental Sciences, McGill University, Saint-Anne-de-Bellevue, QC, Canada
| | - Wei-Cai Zeng
- Antioxidant Polyphenols Team, Department of Food Engineering, Sichuan University, Chengdu, PR China.,The Key Laboratory of Food Science and Technology of Sichuan Province of Education, Sichuan University, Chengdu, PR China
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27
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Kovarik S, Robles R, Schlitz R, Seifert TS, Lorente N, Gambardella P, Stepanow S. Electron Paramagnetic Resonance of Alkali Metal Atoms and Dimers on Ultrathin MgO. Nano Lett 2022; 22:4176-4181. [PMID: 35512394 DOI: 10.1021/acs.nanolett.2c00980] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Electron paramagnetic resonance (EPR) can provide unique insight into the chemical structure and magnetic properties of dopants in oxide and semiconducting materials that are of interest for applications in electronics, catalysis, and quantum sensing. Here, we demonstrate that EPR in combination with scanning tunneling microscopy (STM) allows for probing the bonding and charge state of alkali metal atoms on an ultrathin magnesium oxide layer on a Ag substrate. We observe a magnetic moment of 1 μB for Li2, LiNa, and Na2 dimers corresponding to spin radicals with a charge state of +1e. Single alkali atoms have the same charge state and no magnetic moment. The ionization of the adsorbates is attributed to charge transfer through the oxide to the metal substrate. Our work highlights the potential of EPR-STM to provide insight into dopant atoms that are relevant for the control of the electrical properties of surfaces and nanodevices.
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Affiliation(s)
- Stepan Kovarik
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
| | - Roberto Robles
- Centro de Física de Materiales CFM/MPC (CSIC-UPV/EHU), Paseo Manuel de Lardizabal 5, San Sebastián 20018, Spain
| | - Richard Schlitz
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
| | - Tom Sebastian Seifert
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
- Department of Physics, Freie Universität Berlin, Berlin 14195, Germany
| | - Nicolas Lorente
- Centro de Física de Materiales CFM/MPC (CSIC-UPV/EHU), Paseo Manuel de Lardizabal 5, San Sebastián 20018, Spain
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, San Sebastián 20018, Spain
| | - Pietro Gambardella
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
| | - Sebastian Stepanow
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
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28
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Shurpik DN, Aleksandrova YI, Mostovaya OA, Nazmutdinova VA, Tazieva RE, Murzakhanov FF, Gafurov MR, Zelenikhin PV, Subakaeva EV, Sokolova EA, Gerasimov AV, Gorodov VV, Islamov DR, Cragg PJ, Stoikov II. Self-Healing Thiolated Pillar[5]arene Films Containing Moxifloxacin Suppress the Development of Bacterial Biofilms. Nanomaterials (Basel) 2022; 12:1604. [PMID: 35564312 DOI: 10.3390/nano12091604] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/03/2022] [Accepted: 05/06/2022] [Indexed: 11/17/2022]
Abstract
Polymer self-healing films containing fragments of pillar[5]arene were obtained for the first time using thiol/disulfide redox cross-linking. These films were characterized by thermogravimetric analysis and differential scanning calorimetry, FTIR spectroscopy, and electron microscopy. The films demonstrated the ability to self-heal through the action of atmospheric oxygen. Using UV–vis, 2D 1H-1H NOESY, and DOSY NMR spectroscopy, the pillar[5]arene was shown to form complexes with the antimicrobial drug moxifloxacin in a 2:1 composition (logK11 = 2.14 and logK12 = 6.20). Films containing moxifloxacin effectively reduced Staphylococcus aureus and Klebsiella pneumoniae biofilms formation on adhesive surfaces.
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29
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Qi W, Yadav P, Hong CR, Stevenson RJ, Hay MP, Anderson RF. Spin Trapping Hydroxyl and Aryl Radicals of One-Electron Reduced Anticancer Benzotriazine 1,4-Dioxides. Molecules 2022; 27:812. [PMID: 35164077 DOI: 10.3390/molecules27030812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 02/06/2023] Open
Abstract
Hypoxia in tumors results in resistance to both chemotherapy and radiotherapy treatments but affords an environment in which hypoxia-activated prodrugs (HAP) are activated upon bioreduction to release targeted cytotoxins. The benzotriazine 1,4-di-N-oxide (BTO) HAP, tirapazamine (TPZ, 1), has undergone extensive clinical evaluation in combination with radiotherapy to assist in the killing of hypoxic tumor cells. Although compound 1 did not gain approval for clinical use, it has spurred on the development of other BTOs, such as the 3-alkyl analogue, SN30000, 2. There is general agreement that the cytotoxin(s) from BTOs arise from the one-electron reduced form of the compounds. Identifying the cytotoxic radicals, and whether they play a role in the selective killing of hypoxic tumor cells, is important for continued development of the BTO class of anticancer prodrugs. In this study, nitrone spin-traps, combined with electron spin resonance, give evidence for the formation of aryl radicals from compounds 1, 2 and 3-phenyl analogues, compounds 3 and 4, which form carbon C-centered radicals. In addition, high concentrations of DEPMPO (5-(diethoxyphosphoryl)-5-methyl-1-pyrroline N-oxide) spin-trap the •OH radical. The combination of spin-traps with high concentrations of DMSO and methanol also give evidence for the involvement of strongly oxidizing radicals. The failure to spin-trap methyl radicals with PBN (N-tert-butylphenylnitrone) on the bioreduction of compound 2, in the presence of DMSO, implies that free •OH radicals are not released from the protonated radical anions of compound 2. The spin-trapping of •OH radicals by high concentrations of DEPMPO, and the radical species arising from DMSO and methanol give both direct and indirect evidence for the scavenging of •OH radicals that are involved in an intramolecular process. Hypoxia-selective cytotoxicity is not related to the formation of aryl radicals from the BTO compounds as they are associated with high aerobic cytotoxicity.
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30
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Lai AL, Freed JH. Importance of Negatively Charged Residues in the Membrane Ordering Activity of SARS-CoV-1 and -2 Fusion Peptides. Biophys J 2021; 121:207-227. [PMID: 34929193 PMCID: PMC8683214 DOI: 10.1016/j.bpj.2021.12.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 12/01/2021] [Accepted: 12/16/2021] [Indexed: 11/30/2022] Open
Abstract
Entry of coronaviruses into host cells is mediated by the viral spike (S) protein. Previously, we identified the bona fide FPs for SARS-CoV ("SARS-1") and SARS-CoV-2 ("SARS-2") using ESR spectroscopy. We also found that their FPs induce membrane ordering in a Ca2+-dependent fashion. Here we study which negatively charged residues in SARS-1 FP are involved in this binding, to build a topological model and clarify the role of Ca2+. Our systematic mutation study on the SARS-1 FP shows that all six negatively charged residues contribute to the FP's membrane ordering activity, with D812 the dominant residue. The corresponding SARS-2 residue D830 plays an equivalent role. We provide a topological model of how the FP binds Ca2+ ions: its two segments FP1 and FP2 each bind one Ca2+. The binding of Ca2+, the folding of FP (both studied by ITC experiments), and the ordering activity correlate very well across the mutants, suggesting that the Ca2+ helps the folding of FP in membranes to enhance the ordering activity. Using a novel pseudotyped virus particle (PP)-liposome methodology, we monitored the membrane ordering induced by the FPs in the whole S protein in its trimer form in real time. We found that the SARS-1 and SARS-2 PPs also induce membrane ordering to the extent that separate FPs do, and mutations of the negatively charged residues also significantly suppress the membrane ordering activity. However, the slower kinetics of the FP ordering activity vs. that of the PP suggests the need for initial trimerization of the FPs.
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Affiliation(s)
- Alex L Lai
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, United States
| | - Jack H Freed
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, United States
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31
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Willke P, Bilgeri T, Zhang X, Wang Y, Wolf C, Aubin H, Heinrich A, Choi T. Coherent Spin Control of Single Molecules on a Surface. ACS Nano 2021; 15:17959-17965. [PMID: 34767351 DOI: 10.1021/acsnano.1c06394] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Control of single electron spins constitutes one of the most promising platforms for spintronics, quantum sensing, and quantum information processing. Utilizing single molecular magnets as their hosts establishes an interesting framework since their molecular structure is highly flexible and chemistry-based large-scale synthesis directly provides a way toward scalability. Here, we demonstrate coherent spin manipulation of single molecules on a surface, which we control individually using a scanning tunneling microscope in combination with electron spin resonance. We previously found that iron phthalocyanine (FePc) molecules form a spin-1/2 system when placed on an insulating thin film of magnesium oxide (MgO). Performing Rabi oscillation and Hahn echo measurements, we show that the FePc spin can be coherently manipulated with a phase coherence time T2Echo of several hundreds of nanoseconds. Tunneling current-dependent measurements demonstrate that interaction with the tunneling electrons is the dominating source of decoherence. In addition, we perform Hahn echo measurements on small self-assembled arrays of FePc molecules. We show that, despite additional intermolecular magnetic coupling, spin resonance and T2Echo are much less perturbed by T1 spin flip events of neighboring spins than by the tunneling current. This will potentially allow for individual addressable molecular spins in self-assemblies and with application for quantum information processing.
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Affiliation(s)
- Philip Willke
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, 03760, Republic of Korea
- Ewha Womans University, Seoul, 03760, Republic of Korea
- Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe, 76131, Germany
| | - Tobias Bilgeri
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, 03760, Republic of Korea
- Ewha Womans University, Seoul, 03760, Republic of Korea
- Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland
| | - Xue Zhang
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, 03760, Republic of Korea
- Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Yu Wang
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, 03760, Republic of Korea
- Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Christoph Wolf
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, 03760, Republic of Korea
- Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Herve Aubin
- Centre de Nanosciences et de Nanotechnologies (CNRS), University Paris-Sud, Universités Paris-Saclay, C2N, Palaiseau, 91120, France
| | - Andreas Heinrich
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, 03760, Republic of Korea
- Department of Physics, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Taeyoung Choi
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, 03760, Republic of Korea
- Department of Physics, Ewha Womans University, Seoul, 03760, Republic of Korea
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Lima IS, Guidelli EJ, Baffa O. Dose enhancement factor caused by gold nanoparticles: influence of the dosimetric sensitivity and radiation dose assessed by electron spin resonance dosimetry. Phys Med Biol 2021; 66. [PMID: 34592720 DOI: 10.1088/1361-6560/ac2bb2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 09/30/2021] [Indexed: 11/12/2022]
Abstract
Gold nanoparticles have been extensively used to increase the sensitivity of radiation dosimeters. In this work, nanocomposites of alanine (Ala), 2-methylalanine (2MA), asparagine (Asn) and monosodium glutamate (MSG) containing gold nanoparticles were prepared. The influence of the mass percentage of gold (0.1% up to 3%), absorbed dose (2 Gy-10 kGy) and the intrinsic sensitivity of these materials on the dose enhancement factor (DEF) were investigated. The prepared nanocomposites were characterized by UV-vis absorption spectroscopy and dynamic light scattering technique. Electron spin resonance spectroscopy was employed to assess the dosimetric response. The results revealed that the gold nanoparticles aggregated in the nanocomposites of MSG and Asn but not in the Ala and 2MA samples. Higher DEFs were observed for materials with lower intrinsic sensitivities (Asn and MSG) and for lower doses of radiation, suggesting that the dosimetric response of the nanocomposite dosimeters is governed by the probability of radical recombination. The higher the radiation dose, gold mass percentage and/or intrinsic sensitivity of the dosimetric material, the higher the production of radiation-induced free-radicals, enhancing the probability of radical recombination and resulting in lower DEFs. These results bring new insights about the use of gold nanoparticles to the construction of more sensitive radiation dosimeters.
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Affiliation(s)
- Iara S Lima
- Departamento de Física, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Eder J Guidelli
- Departamento de Física, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Oswaldo Baffa
- Departamento de Física, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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Sichelschmidt J, Gruner T, Das D, Hossain Z. Electron spin resonance of the itinerant ferromagnets LaCrGe 3, CeCrGe 3and PrCrGe 3. J Phys Condens Matter 2021; 33:495605. [PMID: 34534978 DOI: 10.1088/1361-648x/ac27d7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/17/2021] [Indexed: 06/13/2023]
Abstract
We report electron spin resonance of the itinerant ferromagnets LaCrGe3, CeCrGe3, and PrCrGe3. These compounds show well defined and very similar spectra of itinerant Cr 3dspins in the paramagnetic temperature region. Upon cooling and crossing the Cr-ferromagnetic ordering (below around 90 K) strong spectral structures start to dominate the resonance spectra in a quite different manner in the three compounds. In the Ce- and Pr-compounds the resonance is only visible in the paramagnetic region whereas in the La-compound the resonance can be followed far below the ferromagnetic ordering temperature. This behavior will be discussed in terms of the specific interplay between the 4fand 3dmagnetism which appears quite remarkable since CeCrGe3displays heavy fermion behavior even in the magnetically ordered state.
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Affiliation(s)
- Jörg Sichelschmidt
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - Thomas Gruner
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - Debarchan Das
- Department of Physics, Indian Institute of Technology, Kanpur 208016, India
| | - Zakir Hossain
- Department of Physics, Indian Institute of Technology, Kanpur 208016, India
- Institute of Low Temperature and Structure Research, Okólna 2, 50-422 Wroclaw, Poland
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Chede LS, Wagner BA, Buettner GR, Donovan MD. Electron Spin Resonance Evaluation of Buccal Membrane Fluidity Alterations by Sodium Caprylate and L-Menthol. Int J Mol Sci 2021; 22:ijms221910708. [PMID: 34639049 PMCID: PMC8509842 DOI: 10.3390/ijms221910708] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 11/16/2022] Open
Abstract
The ability of sodium caprylate and l-menthol to fluidize phospholipid bilayers composed of lipids simulating the buccal epithelium was investigated using electron spin resonance (ESR) to evaluate the action of these agents as permeation enhancers. 5-Doxyl stearic acid (5-DSA) and 16-doxyl stearic acid (16-DSA) were used as spin labels to identify alterations in membrane fluidity near the polar head groups or inner acyl regions of the lipid bilayer, respectively. The molecular motion of both 5-DSA and 16-DSA showed increased disorder near the polar and inner hydrophobic regions of the bilayer in the presence of sodium caprylate suggesting fluidization in both the regions, which contributes to its permeation enhancing effects. L-menthol decreased the order parameter for 16-DSA, showing membrane fluidization only in the inner acyl regions of the bilayer, which also corresponded to its weaker permeation enhancing effects. The rapid evaluation of changes in fluidity of the bilayer in the presence of potential permeation enhancers using ESR enables improved selection of effective permeation enhancers and enhancer combinations based on their effect on membrane fluidization.
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Affiliation(s)
- Laxmi Shanthi Chede
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA 52242, USA;
| | - Brett A. Wagner
- Free Radical Radiation Biology, The University of Iowa, Iowa City, IA 52242, USA; (B.A.W.); (G.R.B.)
| | - Garry R. Buettner
- Free Radical Radiation Biology, The University of Iowa, Iowa City, IA 52242, USA; (B.A.W.); (G.R.B.)
| | - Maureen D. Donovan
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA 52242, USA;
- Correspondence:
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Tabbì G, Cucci LM, Pinzino C, Munzone A, Marzo T, Pizzanelli S, Satriano C, Magrì A, La Mendola D. Peptides Derived from Angiogenin Regulate Cellular Copper Uptake. Int J Mol Sci 2021; 22:9530. [PMID: 34502439 PMCID: PMC8430698 DOI: 10.3390/ijms22179530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/26/2021] [Accepted: 08/31/2021] [Indexed: 12/31/2022] Open
Abstract
The angiogenin protein (ANG) is one of the most potent endogenous angiogenic factors. In this work we characterized by means of potentiometric, spectroscopic and voltammetric techniques, the copper complex species formed with peptide fragments derived from the N-terminal domain of the protein, encompassing the sequence 1-17 and having free amino, Ang1-17, or acetylated N-terminus group, AcAng1-17, so to explore the role of amino group in metal binding and cellular copper uptake. The obtained data show that amino group is the main copper anchoring site for Ang1-17. The affinity constant values, metal coordination geometry and complexes redox-potentials strongly depend, for both peptides, on the number of copper equivalents added. Confocal laser scanning microscope analysis on neuroblastoma cells showed that in the presence of one equivalent of copper ion, the free amino Ang1-17 increases cellular copper uptake while the acetylated AcAng1-17 strongly decreases the intracellular metal level. The activity of peptides was also compared to that of the protein normally present in the plasma (wtANG) as well as to the recombinant form (rANG) most commonly used in literature experiments. The two protein isoforms bind copper ions but with a different coordination environment. Confocal laser scanning microscope data showed that the wtANG induces a strong increase in intracellular copper compared to control while the rANG decreases the copper signal inside cells. These data demonstrate the relevance of copper complexes' geometry to modulate peptides' activity and show that wtANG, normally present in the plasma, can affect cellular copper uptake.
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Affiliation(s)
- Giovanni Tabbì
- Institute of Crystallography—National Council of Research—CNR, via Paolo Gaifami 18, 95126 Catania, Italy;
| | - Lorena Maria Cucci
- Nano Hybrid BioInterfaces Lab (NHBIL), Department of Chemical Sciences, University of Catania, Viale Andrea Doria 6, 95125 Catania, Italy;
| | - Calogero Pinzino
- Institute for the Chemistry of OrganoMetallic Compounds (ICCOM), National Council of Research—CNR, via G. Moruzzi 1, 56124 Pisa, Italy;
| | - Alessia Munzone
- Aix-Marseille Univesité, 52 Avenue Escadrille Normandie Niemen, 13013 Marseille, France;
| | - Tiziano Marzo
- Department of Pharmacy, University of Pisa, via Bonanno Pisano 6, 56126 Pisa, Italy;
| | - Silvia Pizzanelli
- Institute for the Chemistry of OrganoMetallic Compounds (ICCOM), National Council of Research—CNR, via G. Moruzzi 1, 56124 Pisa, Italy;
| | - Cristina Satriano
- Nano Hybrid BioInterfaces Lab (NHBIL), Department of Chemical Sciences, University of Catania, Viale Andrea Doria 6, 95125 Catania, Italy;
| | - Antonio Magrì
- Institute of Crystallography—National Council of Research—CNR, via Paolo Gaifami 18, 95126 Catania, Italy;
| | - Diego La Mendola
- Department of Pharmacy, University of Pisa, via Bonanno Pisano 6, 56126 Pisa, Italy;
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Jiang X, Boudreau MD, Fu PP, Yin JJ. Applications of electron spin resonance spectroscopy in photoinduced nanomaterial charge separation and reactive oxygen species generation. J Environ Sci Health C Toxicol Carcinog 2021; 39:435-459. [PMID: 35895951 DOI: 10.1080/26896583.2021.1971477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Nano-metals, nano-metal oxides, and carbon-based nanomaterials exhibit superior solar-to-chemical/photo-electron transfer properties and are potential candidates for environmental remediations and energy transfer. Recent research effort focuses on enhancing the efficiency of photoinduced electron-hole separation to improve energy transfer in catalytic reactions. Electron spin resonance (ESR) spectroscopy has been used to monitor the generation of electron/hole and reactive oxygen species (ROS) during nanomaterial-mediated photocatalysis. Using ESR coupled with spin trapping and spin labeling techniques, the underlying photocatalytic mechanism involved in the nanomaterial-mediated photocatalysis was investigated. In this review, we briefly introduced ESR principle and summarized recent advancements using ESR spectroscopy to characterize electron-hole separation and ROS production by different types of nanomaterials.
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Affiliation(s)
- Xiumei Jiang
- Division of Analytical Chemistry, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
| | - Mary D Boudreau
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR, USA
| | - Peter P Fu
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR, USA
| | - Jun-Jie Yin
- Division of Analytical Chemistry, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, USA
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Thorsen MK, Lai A, Lee MW, Hoogerheide DP, Wong GCL, Freed JH, Heldwein EE. Highly Basic Clusters in the Herpes Simplex Virus 1 Nuclear Egress Complex Drive Membrane Budding by Inducing Lipid Ordering. mBio 2021; 12:e0154821. [PMID: 34425706 PMCID: PMC8406295 DOI: 10.1128/mbio.01548-21] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/28/2021] [Indexed: 02/01/2023] Open
Abstract
During replication of herpesviruses, capsids escape from the nucleus into the cytoplasm by budding at the inner nuclear membrane. This unusual process is mediated by the viral nuclear egress complex (NEC) that deforms the membrane around the capsid by oligomerizing into a hexagonal, membrane-bound scaffold. Here, we found that highly basic membrane-proximal regions (MPRs) of the NEC alter lipid order by inserting into the lipid headgroups and promote negative Gaussian curvature. We also find that the electrostatic interactions between the MPRs and the membranes are essential for membrane deformation. One of the MPRs is phosphorylated by a viral kinase during infection, and the corresponding phosphomimicking mutations block capsid nuclear egress. We show that the same phosphomimicking mutations disrupt the NEC-membrane interactions and inhibit NEC-mediated budding in vitro, providing a biophysical explanation for the in vivo phenomenon. Our data suggest that the NEC generates negative membrane curvature by both lipid ordering and protein scaffolding and that phosphorylation acts as an off switch that inhibits the membrane-budding activity of the NEC to prevent capsid-less budding. IMPORTANCE Herpesviruses are large viruses that infect nearly all vertebrates and some invertebrates and cause lifelong infections in most of the world's population. During replication, herpesviruses export their capsids from the nucleus into the cytoplasm by an unusual mechanism in which the viral nuclear egress complex (NEC) deforms the nuclear membrane around the capsid. However, how membrane deformation is achieved is unclear. Here, we show that the NEC from herpes simplex virus 1, a prototypical herpesvirus, uses clusters of positive charges to bind membranes and order membrane lipids. Reducing the positive charge or introducing negative charges weakens the membrane deforming ability of the NEC. We propose that the virus employs electrostatics to deform nuclear membrane around the capsid and can control this process by changing the NEC charge through phosphorylation. Blocking NEC-membrane interactions could be exploited as a therapeutic strategy.
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Affiliation(s)
- Michael K. Thorsen
- Department of Molecular Biology and Microbiology, Graduate Program in Cellular, Molecular and Developmental Biology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Alex Lai
- Department of Chemistry and Chemical Biology and National Biomedical Center for Advanced Electron Spin Resonance Technology, Cornell University, Ithaca, New York, USA
| | - Michelle W. Lee
- Department of Bioengineering, Department of Chemistry and Biochemistry, California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California, USA
| | - David P. Hoogerheide
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Gerard C. L. Wong
- Department of Bioengineering, Department of Chemistry and Biochemistry, California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California, USA
| | - Jack H. Freed
- Department of Chemistry and Chemical Biology and National Biomedical Center for Advanced Electron Spin Resonance Technology, Cornell University, Ithaca, New York, USA
| | - Ekaterina E. Heldwein
- Department of Molecular Biology and Microbiology, Graduate Program in Cellular, Molecular and Developmental Biology, Tufts University School of Medicine, Boston, Massachusetts, USA
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Krasowska J, Pierzchała K, Bzowska A, Forró L, Sienkiewicz A, Wielgus-Kutrowska B. Chromophore of an Enhanced Green Fluorescent Protein Can Play a Photoprotective Role Due to Photobleaching. Int J Mol Sci 2021; 22:ijms22168565. [PMID: 34445269 PMCID: PMC8395242 DOI: 10.3390/ijms22168565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/03/2021] [Accepted: 08/04/2021] [Indexed: 11/16/2022] Open
Abstract
Under stress conditions, elevated levels of cellular reactive oxygen species (ROS) may impair crucial cellular structures. To counteract the resulting oxidative damage, living cells are equipped with several defense mechanisms, including photoprotective functions of specific proteins. Here, we discuss the plausible ROS scavenging mechanisms by the enhanced green fluorescent protein, EGFP. To check if this protein could fulfill a photoprotective function, we employed electron spin resonance (ESR) in combination with spin-trapping. Two organic photosensitizers, rose bengal and methylene blue, as well as an inorganic photocatalyst, nano-TiO2, were used to photogenerate ROS. Spin-traps, TMP-OH and DMPO, and a nitroxide radical, TEMPOL, served as molecular targets for ROS. Our results show that EGFP quenches various forms of ROS, including superoxide radicals and singlet oxygen. Compared to the three proteins PNP, papain, and BSA, EGFP revealed high ROS quenching ability, which suggests its photoprotective role in living systems. Damage to the EGFP chromophore was also observed under strong photo-oxidative conditions. This study contributes to the discussion on the protective function of fluorescent proteins homologous to the green fluorescent protein (GFP). It also draws attention to the possible interactions of GFP-like proteins with ROS in systems where such proteins are used as biological markers.
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Affiliation(s)
- Joanna Krasowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland; (J.K.); (A.B.)
| | - Katarzyna Pierzchała
- Laboratory for Functional and Metabolic Imaging (LIFMET), Institute of Physics (IPHYS), School of Basic Sciences (SB), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland;
- Laboratory of Physics of Complex Matter (LPMC), Institute of Physics (IPHYS), School of Basic Sciences (SB), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland;
| | - Agnieszka Bzowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland; (J.K.); (A.B.)
| | - László Forró
- Laboratory of Physics of Complex Matter (LPMC), Institute of Physics (IPHYS), School of Basic Sciences (SB), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland;
| | - Andrzej Sienkiewicz
- Laboratory of Physics of Complex Matter (LPMC), Institute of Physics (IPHYS), School of Basic Sciences (SB), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland;
- Laboratory for Quantum Magnetism (LQM), Institute of Physics (IPHYS), School of Basic Sciences (SB), École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
- ADSresonances, Route de Genève 60B, CH-1028 Préverenges, Switzerland
- Correspondence: (A.S.); (B.W.-K.)
| | - Beata Wielgus-Kutrowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland; (J.K.); (A.B.)
- Correspondence: (A.S.); (B.W.-K.)
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Lin J, Dai Q, Zhao H, Cao H, Wang T, Wang G, Chen C. Photoinduced Release of Volatile Organic Compounds from Fatty Alcohols at the Air-Water Interface: The Role of Singlet Oxygen Photosensitized by a Carbonyl Group. Environ Sci Technol 2021; 55:8683-8690. [PMID: 33966388 DOI: 10.1021/acs.est.1c00313] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Photoinduced interfacial release of volatile organic compounds (VOCs) from surfactants receives emerging concerns. Here, we investigate the photoreaction of 1-nonanol (NOL) as a model surfactant at the air-water interface, especially for the important role of 1O2 in the formation of VOCs. The production of VOCs is real-time quantitated. The results indicate that the oxygen content apparently affects the total yields of VOCs during the photoreaction of interfacial NOL. The photoactivity of NOL is about 8 times higher under air than that under nitrogen, which is mainly attributed to the generation of 1O2. Additionally, the production of VOCs increased by about 4 times with the existence of the air-water interface. Quenching experiments of 1O2 also illustrate the contribution of 1O2 to VOC formation, which could reach more than 95% during photoirradiation of NOL. Furthermore, density functional theory calculations show that 1O2 generated via energy transfer of photosensitizers can abstract two hydrogen atoms from a fatty alcohol molecule. The energy barrier of this reaction is 72.3 kJ/mol, and its reaction rate coefficient is about 2.742 s-1 M-1. 1O2 significantly promotes photoinduced oxidation of fatty alcohols and VOC formation through hydrogen abstraction, which provides a new insight into the interfacial photoreaction.
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Affiliation(s)
- Jingyi Lin
- Beijing Engineering Research Center of Process Pollution Control, CAS Key Laboratory of Green Process and Engineering, Innovation Academy for Green Manufacture, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Qin Dai
- Beijing Engineering Research Center of Process Pollution Control, CAS Key Laboratory of Green Process and Engineering, Innovation Academy for Green Manufacture, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - He Zhao
- Beijing Engineering Research Center of Process Pollution Control, CAS Key Laboratory of Green Process and Engineering, Innovation Academy for Green Manufacture, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Hongbin Cao
- Beijing Engineering Research Center of Process Pollution Control, CAS Key Laboratory of Green Process and Engineering, Innovation Academy for Green Manufacture, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Tianyu Wang
- Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials, Department of Chemistry, University of Science and Technology Beijing, Beijing 100083, China
| | - Guangwei Wang
- Department of Chemistry School of Science, Tianjin University, Tianjin 300072, China
| | - Chuncheng Chen
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
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Hirayama A, Akazaki S, Nagano Y, Ueda A, Chang-il Lee M, Aoyagi K, Oowada S, Sato K. Hemodialysis raises oxidative stress through carbon-centered radicals despite improved biocompatibility. J Clin Biochem Nutr 2021; 69:44-51. [PMID: 34376913 PMCID: PMC8325767 DOI: 10.3164/jcbn.20-141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/06/2020] [Indexed: 12/13/2022] Open
Abstract
Leukocyte activation and the resulting oxidative stress induced by bioincompatible materials during hemodialysis impact the prognosis of patients. Despite multiple advances in hemodialysis dialyzers, the prognosis of hemodialysis patients with complications deeply related to oxidative stress, such as diabetes mellitus, remains poor. Thus, we re-evaluated the effects of hemodialysis on multiple reactive oxygen species using electron spin resonance-based methods for further improvement of biocompatibility in hemodialysis. We enrolled 31 patients in a stable condition undergoing hemodialysis using high-flux polysulfone dialyzers. The effects of hemodialysis on reactive oxygen species were evaluated by two methods: MULTIS, which evaluates serum scavenging activities against multiple hydrophilic reactive oxygen species, and i-STrap, which detects lipophilic carbon-center radicals. Similar to previous studies, we found that serum hydroxyl radical scavenging activity significantly improved after hemodialysis. Unlike previous studies, we discovered that scavenging activity against alkoxyl radical was significantly reduced after hemodialysis. Moreover, patients with diabetes mellitus showed a decrease in serum scavenging activity against alkyl peroxyl radicals and an increase in lipophilic carbon-center radicals after hemodialysis. These results suggest that despite extensive improvements in dialyzer membranes, the forms of reactive oxygen species that can be eliminated during dialysis are limited, and multiple reactive oxygen species still remain at increased levels during hemodialysis.
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Affiliation(s)
- Aki Hirayama
- Center for Integrative Medicine, Tsukuba University of Technology, 4-12-7 Kasuga, Tsukuba 305-8521, Japan
| | - Satomi Akazaki
- Department of Clinical Biochemistry, Graduate School of Clinical Pharmacy, Kyushu University of Health and Welfare, 1714-1 Yoshino-cho, Nobeoka 882- 8508, Japan
| | - Yumiko Nagano
- Center for Integrative Medicine, Tsukuba University of Technology, 4-12-7 Kasuga, Tsukuba 305-8521, Japan
| | - Atsushi Ueda
- University of Tsukuba Hospital Hitachi Medical Education and Research Center, 2-1-1 Jonan-cho, Hitachi 317-0077, Japan
| | - Masaichi Chang-il Lee
- Yokosuka-Shonan Disaster Health Emergency Research Center & ESR Laboratories, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka 238-8580, Japan
| | - Kazumasa Aoyagi
- Center for Integrative Medicine, Tsukuba University of Technology, 4-12-7 Kasuga, Tsukuba 305-8521, Japan
| | - Shigeru Oowada
- Asao Clinic, 1-8-10 Manpukuji, Asao-ku, Kawasaki 215-0004, Japan
| | - Keizo Sato
- Department of Clinical Biochemistry, Graduate School of Clinical Pharmacy, Kyushu University of Health and Welfare, 1714-1 Yoshino-cho, Nobeoka 882- 8508, Japan
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Abstract
Artificial neural networks are famously opaque—it is often unclear how they work. In this communication, we propose a group-theoretical way of finding out. It reveals considerable internal sophistication, even in simple neural networks: our nets apparently invented an elegant digital filter, a regularized integral transform, and even Chebyshev polynomials. This is a step toward saving reductionism. For centuries, the philosophical approach to science has been to find fundamental laws that govern reality, to test those laws, and to use their predictive power. Black-box neural networks amount to blasphemy within that school, but they are irresistible because they “just work.” Explaining how they work is a notoriously difficult problem, to which this paper offers a partial solution. The lack of interpretability and trust is a much-criticized feature of deep neural networks. In fully connected nets, the signaling between inner layers is scrambled because backpropagation training does not require perceptrons to be arranged in any particular order. The result is a black box; this problem is particularly severe in scientific computing and digital signal processing (DSP), where neural nets perform abstract mathematical transformations that do not reduce to features or concepts. We present here a group-theoretical procedure that attempts to bring inner-layer signaling into a human-readable form, the assumption being that this form exists and has identifiable and quantifiable features—for example, smoothness or locality. We applied the proposed method to DEERNet (a DSP network used in electron spin resonance) and managed to descramble it. We found considerable internal sophistication: the network spontaneously invents a bandpass filter, a notch filter, a frequency axis rescaling transformation, frequency-division multiplexing, group embedding, spectral filtering regularization, and a map from harmonic functions into Chebyshev polynomials—in 10 min of unattended training from a random initial guess.
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Murzakhanov FF, Yavkin BV, Mamin GV, Orlinskii SB, Mumdzhi IE, Gracheva IN, Gabbasov BF, Smirnov AN, Davydov VY, Soltamov VA. Creation of Negatively Charged Boron Vacancies in Hexagonal Boron Nitride Crystal by Electron Irradiation and Mechanism of Inhomogeneous Broadening of Boron Vacancy-Related Spin Resonance Lines. Nanomaterials (Basel) 2021; 11:nano11061373. [PMID: 34067260 PMCID: PMC8224795 DOI: 10.3390/nano11061373] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/18/2021] [Accepted: 05/19/2021] [Indexed: 11/16/2022]
Abstract
Optically addressable high-spin states (S ≥ 1) of defects in semiconductors are the basis for the development of solid-state quantum technologies. Recently, one such defect has been found in hexagonal boron nitride (hBN) and identified as a negatively charged boron vacancy (VB−). To explore and utilize the properties of this defect, one needs to design a robust way for its creation in an hBN crystal. We investigate the possibility of creating VB− centers in an hBN single crystal by means of irradiation with a high-energy (E = 2 MeV) electron flux. Optical excitation of the irradiated sample induces fluorescence in the near-infrared range together with the electron spin resonance (ESR) spectrum of the triplet centers with a zero-field splitting value of D = 3.6 GHz, manifesting an optically induced population inversion of the ground state spin sublevels. These observations are the signatures of the VB− centers and demonstrate that electron irradiation can be reliably used to create these centers in hBN. Exploration of the VB− spin resonance line shape allowed us to establish the source of the line broadening, which occurs due to the slight deviation in orientation of the two-dimensional B-N atomic plains being exactly parallel relative to each other. The results of the analysis of the broadening mechanism can be used for the crystalline quality control of the 2D materials, using the VB− spin embedded in the hBN as a probe.
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Affiliation(s)
- Fadis F. Murzakhanov
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia; (F.F.M.); (B.V.Y.); (G.V.M.); (S.B.O.); (I.E.M.); (I.N.G.); (B.F.G.)
| | - Boris V. Yavkin
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia; (F.F.M.); (B.V.Y.); (G.V.M.); (S.B.O.); (I.E.M.); (I.N.G.); (B.F.G.)
| | - Georgiy V. Mamin
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia; (F.F.M.); (B.V.Y.); (G.V.M.); (S.B.O.); (I.E.M.); (I.N.G.); (B.F.G.)
| | - Sergei B. Orlinskii
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia; (F.F.M.); (B.V.Y.); (G.V.M.); (S.B.O.); (I.E.M.); (I.N.G.); (B.F.G.)
| | - Ivan E. Mumdzhi
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia; (F.F.M.); (B.V.Y.); (G.V.M.); (S.B.O.); (I.E.M.); (I.N.G.); (B.F.G.)
| | - Irina N. Gracheva
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia; (F.F.M.); (B.V.Y.); (G.V.M.); (S.B.O.); (I.E.M.); (I.N.G.); (B.F.G.)
| | - Bulat F. Gabbasov
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia; (F.F.M.); (B.V.Y.); (G.V.M.); (S.B.O.); (I.E.M.); (I.N.G.); (B.F.G.)
| | - Alexander N. Smirnov
- Division of Solid State Physics, Ioffe Institute, Politekhnicheskaya 26, 194021 St. Petersburg, Russia; (A.N.S.); (V.Y.D.)
| | - Valery Yu. Davydov
- Division of Solid State Physics, Ioffe Institute, Politekhnicheskaya 26, 194021 St. Petersburg, Russia; (A.N.S.); (V.Y.D.)
| | - Victor A. Soltamov
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia; (F.F.M.); (B.V.Y.); (G.V.M.); (S.B.O.); (I.E.M.); (I.N.G.); (B.F.G.)
- Correspondence: or ; Tel.: +7-8432-926-480
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Allakhverdiev ES, Maksimov GV, Rodnenkov OV, Luneva OG, Tsoraev GV, Ivanov AD, Yusipovich AI, Martynyuk TV. Effect of Dinitrosyl Iron Complex on Albumin Conformation. Biochemistry (Mosc) 2021; 86:533-539. [PMID: 33993863 DOI: 10.1134/s0006297921050023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Binding of dinitrosyl iron complex (DNIC) to albumin was studied using time-resolved fluorescence (TRF) and electron spin resonance (ESR) spectroscopy. It was found that the fluorescence lifetime of bovine serum albumin (BSA) and human serum albumin (HSA) decreases with binding and depends on DNIC concentration. The observed biexponential pattern of the BSA tryptophan (Trp) fluorescence decay is explained by the presence of two tryptophan residues in the protein molecule. We believe that DNIC forms stable complexes with the cysteine (Cys34) residue in the domain I of albumin. It was shown that the lifetime of albumin tryptophan fluorescence decreased during co-incubation of BSA with DNICs and glutathione. Effects of DNIC on the binding of specific spin-labeled fatty acids with albumin in human blood plasma were studied in vitro. The presence of DNIC in blood plasma does not change conformation of albumin domains II and III. We suggest that the most possible interaction between DNICs and albumin is the formation of a complex; and nitrosylation of the cysteine residue in the albumin domain I occurs without the changes in albumin conformation.
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Affiliation(s)
- Elvin S Allakhverdiev
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia. .,Russian National Medical Research Center of Cardiology, Moscow, 121552, Russia
| | - Georgy V Maksimov
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia. .,Federal State Autonomous Educational Institution of Higher Education "National Research Technological University "MISIS", Moscow, 119049, Russia
| | - Oleg V Rodnenkov
- Russian National Medical Research Center of Cardiology, Moscow, 121552, Russia
| | - Oksana G Luneva
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Georgy V Tsoraev
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Aleksey D Ivanov
- Federal State Autonomous Educational Institution of Higher Education "National Research Technological University "MISIS", Moscow, 119049, Russia
| | | | - Tamila V Martynyuk
- Russian National Medical Research Center of Cardiology, Moscow, 121552, Russia
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Zheng Y, Qiu S, Deng F, Zhu Y, Ma F, Li G. A charcoal-shaped catalyst NiFe 2O 4/Fe 2O 3 in electro-Fenton: high activity, wide pH range and catalytic mechanism. Environ Technol 2021; 42:1996-2008. [PMID: 31672098 DOI: 10.1080/09593330.2019.1687586] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 10/25/2019] [Indexed: 06/10/2023]
Abstract
A charcoal-shaped catalyst NiFe2O4/Fe2O3 in electro-Fenton (EF) was synthesized by a facile precipitation approach via sintering products of oxalate co-precipitation. This obtained NiFe2O4/Fe2O3 catalyst was easily separated via an external magnetic field and was used as a heterogeneous electro-Fenton catalyst for rhodamine B (RhB, a target pollutant) degradation. Characteristics of NiFe2O4/Fe2O3 catalyst were assessed using scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Barrett-Emmett-Teller (BET), respectively. SEM results revealed that the proposed NiFe2O4/Fe2O3 was charcoal-shaped with the size in the range of 0.5-5 μm. Experiment results show that the EF process with the proposed catalyst could work in a wide pH range from 3 to 9. Under optimized conditions, estimated 90% RhB degradation was achieved in 60 min under the following conditions: 0.6 g/L NiFe2O4/Fe2O3, pH 3. Radical scavengers and electron spin resonance (ESR) spectra results demonstrated that the main oxidant species involved was ⋅OH, accounting for RhB degradation in EF. Moreover, according to our research on interfacial reaction, ⋅OH was mainly generated from the homogenous Fenton reaction rather than the surface Fenton reaction, stimulating by the dissolved Fe2+, Fe3+ and Ni2+ from catalyst. The reusability of NiFe2O4/Fe2O3 catalyst was evaluated for recycling the same catalyst for 5 runs. In conclusion, the facile fabrication NiFe2O4/Fe2O3 catalyst shows great potential in wastewater treatment with promising activity.
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Affiliation(s)
- Yanshi Zheng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - Shan Qiu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - Fengxia Deng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - Yingshi Zhu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - Fang Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - Guojun Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
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45
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Cruz SS, Tanygin V, Lear BJ. Asymmetries in the Electronic Properties of Spheroidal Metallic Nanoparticles, Revealed by Conduction Electron Spin Resonance and Surface Plasmon Resonance. ACS Nano 2021; 15:4490-4503. [PMID: 33646754 DOI: 10.1021/acsnano.0c08515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Using electron spin resonance spectroscopy, we demonstrate that the morphological asymmetries present in small spheroidal metallic nanoparticles give rise to asymmetries in the behavior of electrons held in states near the metal's Fermi energy. We find that the effects of morphological asymmetries for these spheroidal systems are more important than the effects of size distributions when explaining the asymmetry in electronic behavior. This is found to be true for all the particles examined, which were made from Cu, Ag, Pd, Ir, Pt, and Au, bearing dodecanethiolate ligands. In the case of the Ag particles, we also demonstrate that the same model used to account for morphological effects in the electron spin resonance spectra can be used to account for small asymmetries present in the plasmon spectrum. This result demonstrates that the electronic properties of even small particles are tunable via morphological changes.
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Affiliation(s)
- Santina S Cruz
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Vadim Tanygin
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Benjamin J Lear
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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46
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Nakayama T, Honda R. Electrochemical and Mechanistic Study of Superoxide Elimination by Mesalazine through Proton-Coupled Electron Transfer. Pharmaceuticals (Basel) 2021; 14:120. [PMID: 33557324 DOI: 10.3390/ph14020120] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 11/17/2022] Open
Abstract
The elimination of superoxide radical anions (O2•−) by 5-amino-2-hydroxybenzoic acid (mesalazine, 5-ASA), 4-amino-2-hydroxybenzoic acid (4-ASA), and related compounds used for ulcerative colitis treatment was investigated using cyclic voltammetry and electron spin resonance (ESR) analyses aided by density functional theory (DFT) calculations. Quasi-reversible O2/O2•− redox was found to be modified by the compounds, suggesting that an acid–base reaction in which a hydroperoxyl radical (HO2•) is formed from O2•− occurs. However, the deprotonated 5-ASA anion can eliminate O2•− through proton-coupled electron transfer (PCET), forming a radical product. This electron transfer (ET) was confirmed by ESR analysis. The 4-aminophenol moiety in 5-ASA plays an important role in the PCET, involving two proton transfers and one ET based on π-conjugation. The electrochemical and DFT results indicated that O2•− elimination by 5-ASA proceeds efficiently through the PCET mechanism after deprotonation of the 1-carboxyl group. Thus, 5-ASA may act as an anti-inflammatory agent in the alkali intestine through PCET-based O2•− elimination.
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47
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Lohmann SH, Trerayapiwat KJ, Niklas J, Poluektov OG, Sharifzadeh S, Ma X. sp3-Functionalization of Single-Walled Carbon Nanotubes Creates Localized Spins. ACS Nano 2020; 14:17675-17682. [PMID: 33306353 DOI: 10.1021/acsnano.0c08782] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Chemical functionalization-introduced sp3 quantum defects in single-walled carbon nanotubes (SWCNTs) have shown compelling optical properties for their potential applications in quantum information science and bioimaging. Here, we utilize temperature- and power-dependent electron spin resonance measurements to study the fundamental spin properties of SWCNTs functionalized with well-controlled densities of sp3 quantum defects. Signatures of isolated spins that are highly localized at the sp3 defect sites are observed, which we further confirm with density functional theory calculations. Applying temperature-dependent line width analysis and power-saturation measurements, we estimate the spin-lattice relaxation time T1 and spin dephasing time T2 to be around 9 μs and 40 ns, respectively. These findings of the localized spin states that are associated with the sp3 quantum defects not only deepen our understanding of the molecular structures of the quantum defects but could also have strong implications for their applications in quantum information science.
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Affiliation(s)
- Sven-Hendrik Lohmann
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | | | - Jens Niklas
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Oleg G Poluektov
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Sahar Sharifzadeh
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
- Division of Materials Science and Engineering and Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215, United States
| | - Xuedan Ma
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60637, United States
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48
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Hori Y, Kubo K, Nishina Y. Unveiling the Mechanism of Polymer Grafting on Graphene for Functional Composites: The Behavior of Radicals. Macromol Rapid Commun 2020; 42:e2000577. [PMID: 33251648 DOI: 10.1002/marc.202000577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/08/2020] [Indexed: 11/07/2022]
Abstract
Polymer-graphene composites have attracted significant attention; however, their formation mechanisms are a focus of debate. This work tries to clarify how grafting occurs on graphene by electron spin resonance techniques. As a result, two pathways are found. One passes through the radicals formed by cleaving CO bonds on graphene are transferred to monomers, then grafting and polymerization proceed. Another mechanism passes through the oxy-radicals, which react with monomers in solution and finally react with carbon radicals on graphene. Based on the mechanism, various types of polymer-graphene composites are prepared, and applied to electrical conductive sheets, basic catalysts, and acidic catalysts.
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Affiliation(s)
- Yuki Hori
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama, 700-8530, Japan.,Research Core for Interdisciplinary Sciences, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama, 700-8530, Japan
| | - Koichiro Kubo
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama, 700-8530, Japan
| | - Yuta Nishina
- Research Core for Interdisciplinary Sciences, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama, 700-8530, Japan
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49
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Horváth E, Rossi L, Mercier C, Lehmann C, Sienkiewicz A, Forró L. Photocatalytic Nanowires-Based Air Filter: Towards Reusable Protective Masks. Adv Funct Mater 2020; 30:2004615. [PMID: 32837497 PMCID: PMC7435547 DOI: 10.1002/adfm.202004615] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/02/2020] [Indexed: 05/19/2023]
Abstract
In the last couple decades, several viral outbreaks resulting in epidemics and pandemics with thousands of human causalities have been witnessed. The current Covid-19 outbreak represents an unprecedented crisis. In stopping the virus' spread, it is fundamental to have personal protective equipment and disinfected surfaces. Here, the development of a TiO2 nanowires (TiO2NWs) based filter is reported, which it is believed will work extremely well for personal protective equipment (PPE), as well as for a new generation of air conditioners and air purifiers. Its efficiency relies on the photocatalytic generation of high levels of reactive oxygen species (ROS) upon UV illumination, and on a particularly high dielectric constant of TiO2, which is of paramount importance for enhanced wettability by the water droplets carrying the germs. The filter pore sizes can be tuned by processing TiO2NWs into filter paper. The kilogram-scale production capability of TiO2NWs gives credibility to its massive application potentials.
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Affiliation(s)
- Endre Horváth
- Laboratory of Physics of Complex MatterEcole Polytechnique Fédérale de LausanneLausanne1015Switzerland
| | - Lídia Rossi
- Laboratory of Physics of Complex MatterEcole Polytechnique Fédérale de LausanneLausanne1015Switzerland
| | - Cyprien Mercier
- Laboratory of Physics of Complex MatterEcole Polytechnique Fédérale de LausanneLausanne1015Switzerland
| | - Caroline Lehmann
- Laboratory of Physics of Living MatterEcole Polytechnique Fédérale de LausanneLausanne1015Switzerland
| | - Andrzej Sienkiewicz
- Laboratory of Physics of Complex MatterEcole Polytechnique Fédérale de LausanneLausanne1015Switzerland
- ADSresonancesPréverenges1028Switzerland
| | - László Forró
- Laboratory of Physics of Complex MatterEcole Polytechnique Fédérale de LausanneLausanne1015Switzerland
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50
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Shankar N, Guimarães AO, Napoli E, Giulivi C. Forensic determination of hair deposition time in crime scenes using electron paramagnetic resonance. J Forensic Sci 2020; 66:72-82. [PMID: 32986869 DOI: 10.1111/1556-4029.14570] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/06/2020] [Accepted: 08/18/2020] [Indexed: 11/28/2022]
Abstract
Several types of biological samples, including hair strands, are found at crime scenes. Apart from the identification of the value and the contributor of the probative evidence, it is important to prove that the time of shedding of hair belonging to a suspect or victim matches the crime window. To this end, to estimate the ex vivo aging of hair, we evaluated time-dependent changes in melanin-derived free radicals in blond, brown, and black hairs by using electron paramagnetic resonance spectroscopy (EPR). Hair strands aged under controlled conditions (humidity 40%, temperature 20-22°C, indirect light, with 12/12 hour of light/darkness cycles) showed a time-dependent decay of melanin-derived radicals. The half-life of eumelanin-derived radicals in hair under our experimental settings was estimated at 22 ± 2 days whereas that of pheomelanin was about 2 days suggesting better stabilization of unpaired electrons by eumelanin. Taken together, this study provides a reference for future forensic studies on determination of degradation of shed hair in a crime scene by following eumelanin radicals by utilizing the non-invasive, non-destructive, and highly specific EPR technique.
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Affiliation(s)
- Nikhita Shankar
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - André O Guimarães
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA.,Laboratório de Ciências Físicas, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ, Brazil
| | - Eleonora Napoli
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - Cecilia Giulivi
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA.,MIND Institute, University of California Davis Medical Center, Sacramento, CA, USA
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