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Xu D, Li J, Liu L, Tang H. Boosting the Optical Trapping of a Single Virus by Quantum Dots Tagging Increases Virus Polarizability and Trap Stiffness. ACS APPLIED MATERIALS & INTERFACES 2023; 15:55174-55182. [PMID: 37966372 DOI: 10.1021/acsami.3c14725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
Optical tweezers use the momentum of photons to capture and manipulate particles in a noncontact way. Although related techniques have been widely used in biology and materials, research on viruses is still relatively limited. It is hard to optically trap viruses because trap stiffness is rather low and the size of viruses is too small. Here, we used an optical tweezers system coupled with a laser confocal fluorescence imaging system, which allows individual viruses to be imaged and trapped in real time and analyzed using multiple parameters in the culture medium. We show that a single virus tagged by quantum dots (QDs) can increase the real part of polarizability, further increasing gradient force and trap stiffness. With this method, we not only can trap and manipulate viruses in real time but also can analyze their interactions with other targets.
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Affiliation(s)
- Dadi Xu
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Jiangtao Li
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Liu Liu
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Hongwu Tang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
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2
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Iyer RR, Sorrells JE, Yang L, Chaney EJ, Spillman DR, Tibble BE, Renteria CA, Tu H, Žurauskas M, Marjanovic M, Boppart SA. Label-free metabolic and structural profiling of dynamic biological samples using multimodal optical microscopy with sensorless adaptive optics. Sci Rep 2022; 12:3438. [PMID: 35236862 PMCID: PMC8891278 DOI: 10.1038/s41598-022-06926-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 02/01/2022] [Indexed: 01/21/2023] Open
Abstract
Label-free optical microscopy has matured as a noninvasive tool for biological imaging; yet, it is criticized for its lack of specificity, slow acquisition and processing times, and weak and noisy optical signals that lead to inaccuracies in quantification. We introduce FOCALS (Fast Optical Coherence, Autofluorescence Lifetime imaging, and Second harmonic generation) microscopy capable of generating NAD(P)H fluorescence lifetime, second harmonic generation (SHG), and polarization-sensitive optical coherence microscopy (OCM) images simultaneously. Multimodal imaging generates quantitative metabolic and morphological profiles of biological samples in vitro, ex vivo, and in vivo. Fast analog detection of fluorescence lifetime and real-time processing on a graphical processing unit enables longitudinal imaging of biological dynamics. We detail the effect of optical aberrations on the accuracy of FLIM beyond the context of undistorting image features. To compensate for the sample-induced aberrations, we implemented a closed-loop single-shot sensorless adaptive optics solution, which uses computational adaptive optics of OCM for wavefront estimation within 2 s and improves the quality of quantitative fluorescence imaging in thick tissues. Multimodal imaging with complementary contrasts improves the specificity and enables multidimensional quantification of the optical signatures in vitro, ex vivo, and in vivo, fast acquisition and real-time processing improve imaging speed by 4-40 × while maintaining enough signal for quantitative nonlinear microscopy, and adaptive optics improves the overall versatility, which enable FOCALS microscopy to overcome the limits of traditional label-free imaging techniques.
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Affiliation(s)
- Rishyashring R. Iyer
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Janet E. Sorrells
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Lingxiao Yang
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Eric J. Chaney
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Darold R. Spillman
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Brian E. Tibble
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991The School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Carlos A. Renteria
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Haohua Tu
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Mantas Žurauskas
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Marina Marjanovic
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Stephen A. Boppart
- grid.35403.310000 0004 1936 9991Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, USA ,grid.35403.310000 0004 1936 9991Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, USA
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3
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Mondal PC, Roy P, Kim D, Fullerton EE, Cohen H, Naaman R. Photospintronics: Magnetic Field-Controlled Photoemission and Light-Controlled Spin Transport in Hybrid Chiral Oligopeptide-Nanoparticle Structures. NANO LETTERS 2016; 16:2806-11. [PMID: 27027885 PMCID: PMC4834632 DOI: 10.1021/acs.nanolett.6b00582] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 03/24/2016] [Indexed: 05/20/2023]
Abstract
The combination of photonics and spintronics opens new ways to transfer and process information. It is shown here that in systems in which organic molecules and semiconductor nanoparticles are combined, matching these technologies results in interesting new phenomena. We report on light induced and spin-dependent charge transfer process through helical oligopeptide-CdSe nanoparticles' (NPs) architectures deposited on ferromagnetic substrates with small coercive force (∼100-200 Oe). The spin control is achieved by the application of the chirality-induced spin-dependent electron transfer effect and is probed by two different methods: spin-controlled electrochemichemistry and photoluminescence (PL) at room temperature. The injected spin could be controlled by excitation of the nanoparticles. By switching the direction of the magnetic field of the substrate, the PL intensity could be alternated.
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Affiliation(s)
| | - Partha Roy
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Dokyun Kim
- Center for Memory and Recording Research, University of California, San Diego, California 92093, United States
| | - Eric E. Fullerton
- Center for Memory and Recording Research, University of California, San Diego, California 92093, United States
| | - Hagai Cohen
- Chemical
Research Support, Weizmann Institute of
Science, Rehovot 76100, Israel
| | - Ron Naaman
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
- E-mail:
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4
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Gaigalas AK, DeRose P, Wang L, Zhang YZ. Optical Properties of CdSe/ZnS Nanocrystals. JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY 2014; 119:610-628. [PMID: 26601047 PMCID: PMC4487276 DOI: 10.6028/jres.119.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 11/10/2014] [Indexed: 06/05/2023]
Abstract
Measurements are presented of the absorbance, fluorescence emission, fluorescence quantum yield, and fluorescence lifetime of CdSe/ZnS nanocrystals, also known as quantum dots (QDs). The study included three groups of nanocrystals whose surfaces were either passivated with organic molecules, modified further with carboxyl groups, or conjugated with CD14 mouse anti-human antibodies. The surface modifications had observable effects on the optical properties of the nanocrystals. The oscillator strength (OS) of the band edge transition was about 1.0 for the nanocrystals emitting at 565 nm, 605 nm, and 655 nm. The OS could not be determined for QDs with emission at 700 nm and 800 nm. The fluorescence lifetimes varied from 26 ns for nanocrystals emitting near 600 nm to 150 ns for nanocrystals emitting near 800 nm. The quantum yield ranged between 0.4 and 0.9 for the nanocrystals in this study. A brightness index (BI) was used to evaluate the suitability of the nanocrystal labels for flow cytometer measurements. Most QD labels are at least as bright as fluorescein for applications in flow cytometer assays with 488 nm excitation. For optimal brightness the QDs should be excited with 405 nm light. We observed a strong dependence of the QD absorbance at 250 nm on the surface modification of the QD.
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Affiliation(s)
| | - Paul DeRose
- National Institute of Standards and Technology, Gaithersburg, MD 20899
| | - Lili Wang
- National Institute of Standards and Technology, Gaithersburg, MD 20899
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5
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Zhao L, Lin Z. Crafting semiconductor organic-inorganic nanocomposites via placing conjugated polymers in intimate contact with nanocrystals for hybrid solar cells. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:4353-4368. [PMID: 22761026 DOI: 10.1002/adma.201201196] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Indexed: 06/01/2023]
Abstract
Semiconductor organic-inorganic hybrid solar cells incorporating conjugated polymers (CPs) and nanocrystals (NCs) offer the potential to deliver efficient energy conversion with low-cost fabrication. The CP-based photovoltaic devices are complimented by an extensive set of advantageous characteristics from CPs and NCs, such as lightweight, flexibility, and solution-processability of CPs, combined with high electron mobility and size-dependent optical properties of NCs. Recent research has witnessed rapid advances in an emerging field of directly tethering CPs on the NC surface to yield an intimately contacted CP-NC nanocomposite possessing a well-defined interface that markedly promotes the dispersion of NCs within the CP matrix, facilitates the photoinduced charge transfer between these two semiconductor components, and provides an effective platform for studying the interfacial charge separation and transport. In this Review, we aim to highlight the recent developments in CP-NC nanocomposite materials, critically examine the viable preparative strategies geared to craft intimate CP-NC nanocomposites and their photovoltaic performance in hybrid solar cells, and finally provide an outlook for future directions of this extraordinarily rich field.
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Affiliation(s)
- Lei Zhao
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
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6
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Song N, Zhu H, Jin S, Lian T. Hole transfer from single quantum dots. ACS NANO 2011; 5:8750-8759. [PMID: 21962001 DOI: 10.1021/nn202713x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Photoinduced hole transfer dynamics from single CdSe/CdS(3ML)/CdZnS(2ML)/ZnS(2ML) core/multishell quantum dots (QDs) to phenothiazine (PTZ) molecules were studied by single QD fluorescence spectroscopy to investigate the static and dynamic heterogeneities of the hole transfer process as well as its effect on the blinking dynamics of QDs. Ensemble-averaged transient absorption and fluorescence decay measurements show that excitons in QDs dissociate by transferring the valence band hole to PTZ with a time constant of 50 ns for the 1:1 PTZ-QD complex, and the subsequent charge recombination process (i.e., electron transfer from the conduction band of the reduced QD to oxidized PTZ to regenerate the complex in the ground state) occurs mainly on the 100 to 1000 ns time scale. Single QD-PTZ complexes show pronounced correlated fluctuations of fluorescence intensity and lifetime with time. In addition to the dynamic fluctuation, there are considerable heterogeneities of average hole transfer rate among different QD-PTZ complexes. The hole transfer process has little effect on the statistics of the off-states, which is often believed to be positively charged QDs with a valence band hole. Instead, it increases the probability of weakly emissive or "gray" states.
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Affiliation(s)
- Nianhui Song
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA
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7
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Ishii K, Tahara T. Resolving inhomogeneity using lifetime-weighted fluorescence correlation spectroscopy. J Phys Chem B 2010; 114:12383-91. [PMID: 20812709 DOI: 10.1021/jp104234c] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Fluorescence correlation spectroscopy (FCS) was extended by incorporating information of the fluorescence lifetime. This new experimental approach, called lifetime-weighted FCS, enables us to observe fluorescence lifetime fluctuations in the nano- to millisecond time region. The potential of this method for resolving inhomogeneity in complex systems was demonstrated. First, by measuring a mixture of two dye molecules having different fluorescence lifetimes, it was shown that the lifetime-weighted correlation deviates from the ordinary intensity correlation only when the system is inhomogeneous. This demonstrated that lifetime-weighted FCS is capable of detecting inhomogeneity in an ensemble-averaged fluorescence decay profile without any a priori knowledge about the system. Second, we applied this method to a dye-labeled polypeptide, a prototypical model of complex biopolymers. It was found that the ratio between the lifetime-weighted and ordinary intensity correlation changes with change of the environment around the polypeptide. This result was interpreted in terms of environment-dependent conformational inhomogeneity of the polypeptide. Delay time dependence of the ratio was found to be constant from ∼1 μs to several milliseconds, indicating that the observed inhomogeneity is persistent in the measured time scale. In combination with fluorescence intensity correlation, lifetime-weighted FCS allows us to examine conformational fluctuations of complex systems in the time region from nano- to milliseconds, being free from the translational diffusion signal.
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Affiliation(s)
- Kunihiko Ishii
- Molecular Spectroscopy Laboratory, Advanced Science Institute (ASI), RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan
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8
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Jin S, Hsiang JC, Zhu H, Song N, Dickson RM, Lian T. Correlated Single Quantum Dot Blinking and Interfacial Electron Transfer Dynamics. Chem Sci 2010; 1:519-526. [PMID: 21915369 PMCID: PMC3170728 DOI: 10.1039/c0sc00334d] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The electron transfer (ET) dynamics from core/multi-shell (CdSe/CdS(3ML)ZnCdS(2ML)ZnS(2ML)) quantum dots (QDs) to adsorbed Fluorescein (F27) molecules have been studied by single particle spectroscopy to probe the relationship between single QD interfacial electron transfer and blinking dynamics. Electron transfer from the QD to F27 and the subsequent recombination were directly observed by ensemble-averaged transient absorption spectroscopy. Single QD-F27 complexes show correlated fluctuation of fluorescence intensity and lifetime, similar to those observed in free QDs. With increasing ET rate (controlled by F27-to-QD ratio), the lifetime of on states decreases and relative contribution of off states increases. It was shown that ET is active for QDs in on states, the excited state lifetime of which reflects the ET rate, whereas in the off state QD excitons decay by Auger relaxation and ET is not a competitive quenching pathway. Thus, the blinking dynamics of single QDs modulate their interfacial ET activity. Furthermore, interfacial ET provides an additional pathway for generating off states, leading to correlated single QD interfacial ET and blinking dynamics in QD-acceptor complexes. Because blinking is a general phenomenon of single QDs, it appears that the correlated interfacial ET and blinking and the resulting intermittent ET activity are general phenomena for single QDs.
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Affiliation(s)
- Shengye Jin
- Department of Chemistry, Emory University, Atlanta, GA, 30322
| | - Jung-Cheng Hsiang
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332-0400
| | - Haiming Zhu
- Department of Chemistry, Emory University, Atlanta, GA, 30322
| | - Nianhui Song
- Department of Chemistry, Emory University, Atlanta, GA, 30322
| | - Robert M. Dickson
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332-0400
| | - Tianquan Lian
- Department of Chemistry, Emory University, Atlanta, GA, 30322
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9
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Jin S, Song N, Lian T. Suppressed blinking dynamics of single QDs on ITO. ACS NANO 2010; 4:1545-1552. [PMID: 20170100 DOI: 10.1021/nn901808f] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The exciton quenching dynamics of single CdSe/CdS(3ML)ZnCdS(2ML)ZnS(2ML) core/multishell QDs adsorbed on glass, In2O3, and ITO have been compared. Single QDs on In2O3 show shorter fluorescence lifetimes and higher blinking frequencies than those on glass because of interfacial electron transfer from QDs to In2O3. Compared to glass and In2O3, single QDs on ITO show suppressed blinking activity as well as reduced fluorescence lifetimes. For QDs in contact with the n-doped ITO, the equilibration of their Fermi levels leads to the formation of negatively charged QDs. In these negatively charged QDs, the off states are suppressed because of the effective removal of the valence band holes, and their fluorescence lifetimes are shortened because of exciton Auger recombination and hole transfer processes involving the additional electrons. This study shows that the blinking of single QDs can be effectively suppressed on the surface of ITO. This phenomenon may also be observable for other QDs and on different n-doped semiconductors.
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Affiliation(s)
- Shengye Jin
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA
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10
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Semiconductor Nanocrystals Hybridized with Functional Ligands: New Composite Materials with Tunable Properties. MATERIALS 2010. [PMCID: PMC5525183 DOI: 10.3390/ma3010614] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Semiconductor nanocrystals hybridized with functional ligands represent an important new class of composite nanomaterials. The development of these new nanoscale building blocks has intensified over the past few years and offer significant advantages in a wide array of applications. Functional ligands allow for incorporation of nanocrystals into areas where their unique photophysics can be exploited. Energy and charge transfer between the ligands and the nanocrystal also result in enhanced physical properties that can be tuned by the choice of ligand architecture. Here, progress in the development and applications involving this new class of composite materials will be discussed.
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11
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Baker TA, Rouge JL, Nesbitt DJ. Single molecule studies of quantum dot fluorescence intermittency: evidence for both dark and light-assisted blinking dynamics. Mol Phys 2009. [DOI: 10.1080/00268970902933820] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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Hassey-Paradise R, Cyphersmith A, Tilley AM, Mortsolf T, Basak D, Venkataraman D, Barnes MD. Dissymmetries in fluorescence excitation and emission from single chiral molecules. Chirality 2009; 21 Suppl 1:E265-76. [DOI: 10.1002/chir.20809] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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13
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Fu Y, Zhang J, Lakowicz JR. Silver-enhanced fluorescence emission of single quantum dot nanocomposites. Chem Commun (Camb) 2008:313-5. [PMID: 19209313 DOI: 10.1039/b816736b] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel plasmon-coupled quantum dot (QD) nanocomposite via covalently interfacing the QD surfaces with silver nanoparticles was developed with greatly reduced blinking and enhanced emission fluorescence.
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Affiliation(s)
- Yi Fu
- Center for Fluorescence Spectroscopy, University of Maryland School of Medicine, 725 W. Lombard Street, Baltimore, MD 21201, USA
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14
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Munro AM, Ginger DS. Photoluminescence quenching of single CdSe nanocrystals by ligand adsorption. NANO LETTERS 2008; 8:2585-2590. [PMID: 18578549 DOI: 10.1021/nl801132t] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We study the effects of octadecanethiol on the photoluminescence intensity and blinking dynamics of single CdSe nanocrystal quantum dots. The number of luminescent nanocrystals per unit area, the intensity histograms of the luminescent nanocrystals, and the single nanocrystal blinking behavior are analyzed in samples with and without added octadecanethiol. We find that the individual nanocrystals within an ensemble do not quench uniformly with thiol addition. The data suggest that the binding of a single octadecanethiol molecule to a CdSe nanocrystal can decrease the photoluminescence quantum yield of that single nanocrystal by at least 50%. These results are important for interpreting photoluminescence-based studies of nanocrystal-ligand binding constants and surface chemistry.
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Affiliation(s)
- Andrea M Munro
- University of Washington, Department of Chemistry, Seattle, Washington 98195-1700, USA
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