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Peña Román RJ, Auad Y, Grasso L, Padilha LA, Alvarez F, Barcelos ID, Kociak M, Zagonel LF. Design and implementation of a device based on an off-axis parabolic mirror to perform luminescence experiments in a scanning tunneling microscope. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2022; 93:043704. [PMID: 35489916 DOI: 10.1063/5.0078423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 02/27/2022] [Indexed: 06/14/2023]
Abstract
We present the design, implementation, and illustrative results of a light collection/injection strategy based on an off-axis parabolic mirror collector for a low-temperature Scanning Tunneling Microscope (STM). This device allows us to perform STM induced Light Emission (STM-LE) and Cathodoluminescence (STM-CL) experiments and in situ Photoluminescence (PL) and Raman spectroscopy as complementary techniques. Considering the Étendue conservation and using an off-axis parabolic mirror, it is possible to design a light collection and injection system that displays 72% of collection efficiency (considering the hemisphere above the sample surface) while maintaining high spectral resolution and minimizing signal loss. The performance of the STM is tested by atomically resolved images and scanning tunneling spectroscopy results on standard sample surfaces. The capabilities of our system are demonstrated by performing STM-LE on metallic surfaces and two-dimensional semiconducting samples, observing both plasmonic and excitonic emissions. In addition, we carried out in situ PL measurements on semiconducting monolayers and quantum dots and in situ Raman on graphite and hexagonal boron nitride (h-BN) samples. Additionally, STM-CL and PL were obtained on monolayer h-BN gathering luminescence spectra that are typically associated with intragap states related to carbon defects. The results show that the flexible and efficient light injection and collection device based on an off-axis parabolic mirror is a powerful tool to study several types of nanostructures with multiple spectroscopic techniques in correlation with their morphology at the atomic scale and electronic structure.
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Affiliation(s)
- Ricardo Javier Peña Román
- "Gleb Wataghin" Institute of Physics, University of Campinas-UNICAMP, 13083-859 Campinas, SP, Brazil
| | - Yves Auad
- "Gleb Wataghin" Institute of Physics, University of Campinas-UNICAMP, 13083-859 Campinas, SP, Brazil
| | - Lucas Grasso
- "Gleb Wataghin" Institute of Physics, University of Campinas-UNICAMP, 13083-859 Campinas, SP, Brazil
| | - Lazaro A Padilha
- "Gleb Wataghin" Institute of Physics, University of Campinas-UNICAMP, 13083-859 Campinas, SP, Brazil
| | - Fernando Alvarez
- "Gleb Wataghin" Institute of Physics, University of Campinas-UNICAMP, 13083-859 Campinas, SP, Brazil
| | - Ingrid David Barcelos
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), 13083-970 Campinas, SP, Brazil
| | - Mathieu Kociak
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - Luiz Fernando Zagonel
- "Gleb Wataghin" Institute of Physics, University of Campinas-UNICAMP, 13083-859 Campinas, SP, Brazil
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Mundoor H, Cruz-Colón EM, Park S, Liu Q, Smalyukh II, van de Lagemaat J. Control of quantum dot emission by colloidal plasmonic pyramids in a liquid crystal. OPTICS EXPRESS 2020; 28:5459-5469. [PMID: 32121766 DOI: 10.1364/oe.383672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/25/2020] [Indexed: 06/10/2023]
Abstract
We study the plasmon-enhanced fluorescence of a single semiconducting quantum dot near the apex of a colloidal gold pyramid spatially localized by the elastic forces of the liquid crystal host. The gold pyramid particles were manipulated within the liquid crystal medium by laser tweezers, enabling the self-assembly of a semiconducting quantum dot dispersed in the medium near the apex of the gold pyramid, allowing us to probe the plasmon-exciton interactions. We demonstrate the effect of plasmon coupling on the fluorescence lifetime and the blinking properties of the quantum dot. Our results demonstrate that topological defects around colloidal particles in liquid crystal combined with laser tweezers provide a platform for plasmon exciton interaction studies and potentially could be extended to the scale of composite materials for nanophotonic applications.
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Dinel M, Tartaggia S, Wallace GQ, Boudreau D, Masson J, Polo F. The Fundamentals of Real‐Time Surface Plasmon Resonance/Electrogenerated Chemiluminescence. Angew Chem Int Ed Engl 2019; 58:18202-18206. [DOI: 10.1002/anie.201909806] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 09/30/2019] [Indexed: 12/26/2022]
Affiliation(s)
- Marie‐Pier Dinel
- Department of ChemistryUniversité de Montréal C.P. 6128 Succ. Centre-Ville Montreal Qc H3C 3J7 Canada
| | - Stefano Tartaggia
- Farmacologia Sperimentale e ClinicaIRCCS Centro di Riferimento Oncologico Via Franco Gallini 2 33081 Aviano Italy
| | - Gregory Q. Wallace
- Department of ChemistryUniversité de Montréal C.P. 6128 Succ. Centre-Ville Montreal Qc H3C 3J7 Canada
| | - Denis Boudreau
- Department of Chemistry and Centre for Optics, Photonics and Lasers (COPL)Université Laval 1045, av. de la Médecine Québec Qc G1V 0A6 Canada
| | - Jean‐Francois Masson
- Department of ChemistryUniversité de Montréal C.P. 6128 Succ. Centre-Ville Montreal Qc H3C 3J7 Canada
| | - Federico Polo
- Department of Molecular Sciences and NanosystemsCa' Foscari University of Venice Via Torino 155B 30172 Venezia Italy
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Dinel M, Tartaggia S, Wallace GQ, Boudreau D, Masson J, Polo F. The Fundamentals of Real‐Time Surface Plasmon Resonance/Electrogenerated Chemiluminescence. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201909806] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Marie‐Pier Dinel
- Department of ChemistryUniversité de Montréal C.P. 6128 Succ. Centre-Ville Montreal Qc H3C 3J7 Canada
| | - Stefano Tartaggia
- Farmacologia Sperimentale e ClinicaIRCCS Centro di Riferimento Oncologico Via Franco Gallini 2 33081 Aviano Italy
| | - Gregory Q. Wallace
- Department of ChemistryUniversité de Montréal C.P. 6128 Succ. Centre-Ville Montreal Qc H3C 3J7 Canada
| | - Denis Boudreau
- Department of Chemistry and Centre for Optics, Photonics and Lasers (COPL)Université Laval 1045, av. de la Médecine Québec Qc G1V 0A6 Canada
| | - Jean‐Francois Masson
- Department of ChemistryUniversité de Montréal C.P. 6128 Succ. Centre-Ville Montreal Qc H3C 3J7 Canada
| | - Federico Polo
- Department of Molecular Sciences and NanosystemsCa' Foscari University of Venice Via Torino 155B 30172 Venezia Italy
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5
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Edelmann K, Gerhard L, Winkler M, Wilmes L, Rai V, Schumann M, Kern C, Meyer M, Wegener M, Wulfhekel W. Light collection from a low-temperature scanning tunneling microscope using integrated mirror tips fabricated by direct laser writing. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:123107. [PMID: 30599551 DOI: 10.1063/1.5053882] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 11/08/2018] [Indexed: 05/24/2023]
Abstract
We report on a cryogenic scanning tunneling microscope (STM) designed for single molecule studies, in which the light emitted from the tunneling junction is collected by an integrated optics on the tip. Using direct laser writing, the tip and the surrounding microscopic parabolic mirror are fabricated as one piece, which is small enough to collimate the collected light directly into an optical multimode fiber fixed inside the STM. This simple and compact setup combines high collection efficiency and ease of handling while not interfering with the cryostat operation, allowing uninterrupted measurements at 1.4 K for up to 5 days with low drift.
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Affiliation(s)
- Kevin Edelmann
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
| | - Lukas Gerhard
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
| | - Moritz Winkler
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
| | - Lars Wilmes
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
| | - Vibhuti Rai
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
| | - Martin Schumann
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
| | - Christian Kern
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
| | - Michael Meyer
- Physikalisches Institut, Karlsruhe Institute of Technology (KIT), D-76131 Karlsruhe, Germany
| | - Martin Wegener
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
| | - Wulf Wulfhekel
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany
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Lee YS, Bu HB, Taniguchi T, Takagi T, Sobue S, Yamada H, Iwaki T, Kim D. Hydrothermal Synthesis of NAC-capped II–VI Semiconductor ZnSe Quantum Dots in Acidic Condition. CHEM LETT 2016. [DOI: 10.1246/cl.160431] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Maturova K, Nanayakkara SU, Luther JM, van de Lagemaat J. Fast current blinking in individual PbS and CdSe quantum dots. NANO LETTERS 2013; 13:2338-2345. [PMID: 23472703 DOI: 10.1021/nl3036096] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Fast current intermittency of the tunneling current through single semiconductor quantum dots was observed through time-resolved intermittent contact conductive atomic force microscopy in the dark and under illumination at room temperature. The current through a single dot switches on and off at time scales ranging from microseconds to seconds with power-law distributions for both the on and off times. On states are attributed to the resonant tunneling of charges from the electrically conductive AFM tip to the quantum dot, followed by transfer to the substrate, whereas off states are attributed to a Coulomb blockade effect in the quantum dots that shifts the energy levels out of resonance conditions due to the presence of the trapped charge, while at the same bias. The observation of current intermittency due to Coulomb blockade effects has important implications for the understanding of carrier transport through arrays of quantum dots.
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Affiliation(s)
- Klara Maturova
- Chemical and Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA
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Ding H, Wu F. Image guided biodistribution and pharmacokinetic studies of theranostics. Am J Cancer Res 2012; 2:1040-53. [PMID: 23227121 PMCID: PMC3516836 DOI: 10.7150/thno.4652] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 06/17/2012] [Indexed: 11/05/2022] Open
Abstract
Image guided technique is playing an increasingly important role in the investigation of the biodistribution and pharmacokinetics of drugs or drug delivery systems in various diseases, especially cancers. Besides anatomical imaging modalities such as computed tomography (CT), magnetic resonance imaging (MRI), molecular imaging strategy including optical imaging, positron emission tomography (PET) and single-photon emission computed tomography (SPECT) will facilitate the localization and quantization of radioisotope or optical probe labeled nanoparticle delivery systems in the category of theranostics. The quantitative measurement of the bio-distribution and pharmacokinetics of theranostics in the fields of new drug/probe development, diagnosis and treatment process monitoring as well as tracking the brain-blood-barrier (BBB) breaking through by high sensitive imaging method, and the applications of the representative imaging modalities are summarized in this review.
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Gao B, Kuang YM, Liao Y, Dong ZC. Dispersion and STM Characterization of Au-CdSe Nanohybrids on Au(111). CHINESE J CHEM PHYS 2012. [DOI: 10.1088/1674-0068/25/02/231-234] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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10
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Lutz T, Kabakchiev A, Dufaux T, Wolpert C, Wang Z, Burghard M, Kuhnke K, Kern K. Scanning tunneling luminescence of individual CdSe nanowires. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2011; 7:2396-2400. [PMID: 21678550 DOI: 10.1002/smll.201100434] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Indexed: 05/30/2023]
Abstract
The local luminescence properties of individual CdSe nanowires composed of segments of zinc blende and wurtzite crystal structures are investigated by low-temperature scanning tunneling luminescence spectroscopy. Light emission from the wires is achieved by the direct injection of holes and electrons, without the need for coupling to tip-induced plasmons in the underlying metal substrate. The photon energy is found to increase with decreasing wire diameter due to exciton confinement. The bulk bandgap extrapolated from the energy versus diameter dependence is consistent with photon emission from the zinc blende-type CdSe sections.
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Affiliation(s)
- Theresa Lutz
- Max-Planck-Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany.
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11
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Surface-engineered quantum dots for the labeling of hydrophobic microdomains in bacterial biofilms. Biomaterials 2011; 32:5459-70. [DOI: 10.1016/j.biomaterials.2011.04.019] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Accepted: 04/05/2011] [Indexed: 11/22/2022]
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12
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Aboulaich A, Geszke M, Balan L, Ghanbaja J, Medjahdi G, Schneider R. Water-based route to colloidal Mn-doped ZnSe and core/shell ZnSe/ZnS quantum dots. Inorg Chem 2010; 49:10940-8. [PMID: 21049903 DOI: 10.1021/ic101302q] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Relatively monodisperse and highly luminescent Mn(2+)-doped zinc blende ZnSe nanocrystals were synthesized in aqueous solution at 100 °C using the nucleation-doping strategy. The effects of the experimental conditions and of the ligand on the synthesis of nanocrystals were investigated systematically. It was found that there were significant effects of molar ratio of precursors and heating time on the optical properties of ZnSe:Mn nanocrystals. Using 3-mercaptopropionic acid as capping ligand afforded 3.1 nm wide ZnSe:Mn quantum dots (QDs) with very low surface defect density and which exhibited the Mn(2+)-related orange luminescence. The post-preparative introduction of a ZnS shell at the surface of the Mn(2+)-doped ZnSe QDs improved their photoluminescence properties, resulting in stronger emission. A 2.5-fold increase in photoluminescence quantum yield (from 3.5 to 9%) and of Mn(2+) ion emission lifetime (from 0.62 to 1.39 ms) have been observed after surface passivation. The size and the structure of these QDs were also corroborated by using transmission electron microscopy, energy dispersive spectroscopy, and X-ray powder diffraction.
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Affiliation(s)
- Abdelhay Aboulaich
- Laboratoire Réactions et Génie des Procédés (LRGP), UPR 3349, Nancy-University, CNRS, 1 rue Grandville, 54001 Nancy Cedex, France
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13
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Coulon J, Thouvenin I, Aldeek F, Balan L, Schneider R. Glycosylated quantum dots for the selective labelling of Kluyveromyces bulgaricus and Saccharomyces cerevisiae yeast strains. J Fluoresc 2010; 20:591-7. [PMID: 20058182 DOI: 10.1007/s10895-009-0590-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 12/22/2009] [Indexed: 11/29/2022]
Abstract
Highly fluorescent CdTe quantum dots (QDs) stabilized by thioglycolic acid (TGA) were prepared by an aqueous solution approach and used as fluorescent labels in detecting yeast cells. Sugars (mannose, galactose or glucose) were adsorbed on CdTe@TGA QDs and the interaction of these nanoparticles with yeast cells was studied by fluorescence microscopy. Results obtained demonstrate that galactose and mannose functionalized QDs associate respectively with Kluyveromyces bulgaricus and Saccharomyces cerevisiae yeast strains due to saccharide/lectin specific recognition. Glucose-functionalized CdTe QDs, which are not recognized by cell lectins, preferentially localize in the bud scars of S. cerevisiae.
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Affiliation(s)
- Joël Coulon
- LCPME, Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, Nancy-University, CNRS, 405 rue de Vandoeuvre, 54600 Villers-lès-Nancy, France.
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14
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Romero MJ, Morfa AJ, Reilly TH, van de Lagemaat J, Al-Jassim M. Nanoscale imaging of exciton transport in organic photovoltaic semiconductors by tip-enhanced tunneling luminescence. NANO LETTERS 2009; 9:3904-3908. [PMID: 19751068 DOI: 10.1021/nl902105f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In organic solar cells, the efficiency of the exciton transport and dissociation across donor-acceptor (D/A) interfaces is controlled by the nanoscale distribution of the donor and acceptor phases. The observation of photoluminescence quenching is often used as confirmation for efficient exciton dissociation but provides no information on the nanoscopic nature of the exciton transport. Here we demonstrate nanoscale imaging of the exciton transport in films consisting of the conjugated polymer poly(3-hexylthiophene) (P3HT, electron donor) blended with the C60 derivative 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM, electron acceptor) by a tunneling luminescence spectroscopy based on atomic force microscopy. The excitonic luminescence is significantly enhanced when the conjugated polymer is coupled to the plasmon excitation at the tip (tip-enhanced luminescence). This effect allows one to dramatically improve the detection efficiency of the excitonic luminescence and, consequently, resolve individual domains of the conjugated polymer in which the exciton will recombine before dissociation at the D/A interface. Under thermal annealing conditions promoting the segregation of the donor and acceptor phases, a clear increase of the luminescence is seen from polymer-rich regions, consistent with domains of dimensions much larger than the exciton diffusion length. The described scanning luminescence microscopy can thus be applied to the optimization of the blends used in solar cells.
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Affiliation(s)
- Manuel J Romero
- National Renewable Energy Laboratory (NREL), 1617 Cole Boulevard, Golden, Colorado 80401-3393,USA.
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Choi Y, Park Y, Kang T, Lee LP. Selective and sensitive detection of metal ions by plasmonic resonance energy transfer-based nanospectroscopy. NATURE NANOTECHNOLOGY 2009; 4:742-6. [PMID: 19893511 DOI: 10.1038/nnano.2009.258] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2009] [Accepted: 07/31/2009] [Indexed: 05/04/2023]
Abstract
Highly selective and sensitive optical methods for the detection of metal ions have had a substantial impact on molecular biology, environmental monitoring and other areas of research. Here we demonstrate a new method for detecting metal ions that is based on selective plasmonic resonance energy transfer (PRET) between conjugated metal-ligand complexes and a single gold nanoplasmonic probe. In addition to offering high spatial resolution due to the small size of the probe, our method is 100 to 1,000 times more sensitive than organic reporter-based methods. Moreover, it can achieve high selectivity owing to the selective formation of Cu(2+) complexes and selective resonant quenching of the gold nanoplasmonic probe by the conjugated complexes. We expect that PRET-based metal ion sensing could have applications in cellular imaging, systems biology and environmental monitoring.
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Affiliation(s)
- Yeonho Choi
- Biomolecular Nanotechnology Center, Berkeley Sensor and Actuator Center, Department of Bioengineering, University of California at Berkeley, Berkeley, CA 94720, USA
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Yong KT, Ding H, Roy I, Law WC, Bergey EJ, Maitra A, Prasad PN. Imaging pancreatic cancer using bioconjugated InP quantum dots. ACS NANO 2009; 3:502-10. [PMID: 19243145 PMCID: PMC2762404 DOI: 10.1021/nn8008933] [Citation(s) in RCA: 176] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
In this paper, we report the successful use of non-cadmium-based quantum dots (QDs) as highly efficient and nontoxic optical probes for imaging live pancreatic cancer cells. Indium phosphide (core)-zinc sulfide (shell), or InP/ZnS, QDs with high quality and bright luminescence were prepared by a hot colloidal synthesis method in nonaqueous media. The surfaces of these QDs were then functionalized with mercaptosuccinic acid to make them highly dispersible in aqueous media. Further bioconjugation with pancreatic cancer specific monoclonal antibodies, such as anticlaudin 4 and antiprostate stem cell antigen (anti-PSCA), to the functionalized InP/ZnS QDs, allowed specific in vitro targeting of pancreatic cancer cell lines (both immortalized and low passage ones). The receptor-mediated delivery of the bioconjugates was further confirmed by the observation of poor in vitro targeting in nonpancreatic cancer based cell lines which are negative for the claudin-4-receptor. These observations suggest the immense potential of InP/ZnS QDs as non-cadmium-based safe and efficient optical imaging nanoprobes in diagnostic imaging, particularly for early detection of cancer.
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Affiliation(s)
- Ken-Tye Yong
- Institute for Lasers, Photonics and Biophotonics, University at Buffalo, The State University of New York, Buffalo, New York 14260-4200, USA.
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Liu GL, Long YT, Choi Y, Kang T, Lee LP. Quantized plasmon quenching dips nanospectroscopy via plasmon resonance energy transfer. Nat Methods 2007; 4:1015-7. [DOI: 10.1038/nmeth1133] [Citation(s) in RCA: 259] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Accepted: 10/30/2007] [Indexed: 11/09/2022]
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