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Akaishi Y, Mokhtar A, Shimoyoshi M, Nohara T, Inomata Y, Kosumi D, Fukaminato T, Kida T. Light-Stimulated Luminescence Control of Lead Halide-Based Perovskite Nanocrystals Coupled with Photochromic Molecules via Electron and Energy Transfer. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2205046. [PMID: 36310113 DOI: 10.1002/smll.202205046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/06/2022] [Indexed: 06/16/2023]
Abstract
Photoswitchable nanomaterials are key materials in the development of advanced imaging techniques, such as super-resolution fluorescence microscopy. The combination of perovskite CsPbBr3 nanocrystals (NCs) with bright photoluminescence (PL) emission and diarylethenes (DAEs) with structural changes in response to ultraviolet (UV) and visible light is a promising candidate system. Herein, CsPbBr3 NCs are coupled with photochromic DAE molecules to control the PL emission from the NCs by light stimulation. The PL emission is successfully switched ON and OFF by alternating UV and visible light irradiation. Time-resolved PL emission studies suggest that Förster resonance energy transfer from CsPbBr3 NCs to the closed-ring form of DAE occurs after UV irradiation, and the PL emission is quenched. Upon visible-light irradiation, DAE is converted to the open-ring isomer, and the PL emission is restored. Femtosecond pump-probe spectroscopy reveals that light stimulation induces not only energy transfer but also photoinduced electron transfer in the NC-DAE pair on the picosecond timescale to form DAE radicals. Thus, it is suggested that the holes residing in the NCs react with the NCs, degrading the PL emission. Stable PL switching is realized using 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) as a hole scavenger to avoid the reaction between the holes and NCs.
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Affiliation(s)
- Yuji Akaishi
- Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Ashkan Mokhtar
- Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Manami Shimoyoshi
- Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Taiki Nohara
- Department of Physics, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Yusuke Inomata
- Faculty of Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Daisuke Kosumi
- Department of Physics, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
- Institute of Industrial Nanomaterials, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Tuyoshi Fukaminato
- Faculty of Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Tetsuya Kida
- Faculty of Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
- Institute of Industrial Nanomaterials, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
- International Research Organization for Advanced Science and Technology (IROAST), Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
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2
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Ceresa L, Chavez J, Kitchner E, Kimball J, Gryczynski I, Gryczynski Z. Imaging and detection of long-lived fluorescence probes in presence of highly emissive and scattering background. Exp Biol Med (Maywood) 2022; 247:1840-1851. [PMID: 35938479 PMCID: PMC9679360 DOI: 10.1177/15353702221112121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Optical biomedical imaging and diagnostics is a rapidly growing field that provides both structural and functional information with uses ranging from fundamental to practical clinical applications. Nevertheless, imaging/visualizing fluorescence objects with high spatial resolution in a highly scattering and emissive biological medium continues to be a significant challenge. A fundamental limiting factor for imaging technologies is the signal-to-background ratio (SBR). For a long time to improve the SBR, we tried to improve the brightness of fluorescence probes. Many novel fluorophores with improved brightness (almost reaching the theoretical limit), redshifted emission, highly improved photostability, and biocompatibility greatly helped advance fluorescence detection and imaging. However, autofluorescence, scattering of excitation light, and Raman scattering remain fundamental limiting problems that drastically limit detection sensitivity. Similarly, significant efforts were focused on reducing the background. High-quality sample purification eliminates the majority of autofluorescence background and in a limited confocal volume allows detection to reach the ultimate sensitivity to a single molecule. However, detection and imaging in physiological conditions does not allow for any sample (cells or tissue) purification, forcing us to face a fundamental limitation. A significant improvement in limiting background can be achieved when fluorophores with a long fluorescence lifetime are used, and time-gated detection is applied. However, all long-lived fluorophores present low brightness, limiting the potential improvement. We recently proposed to utilize multipulse excitation (burst of pulses) to enhance the relative signal of long-lived fluorophores and significantly improve the SBR. Herein, we present results obtained with multipulse excitation and compare them with standard single-pulse excitation. Subtraction of images obtained with a single pulse from those obtained with pulse burst (differential image) highly limits background and instrumental noise resulting in more specific/sensitive detection and allows to achieve greater imaging depth in highly scattering media, including skin and tissue.
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Adhikari DP, Biener G, Stoneman MR, Badu DN, Paprocki JD, Eis A, Park PSH, Popa I, Raicu V. Comparative photophysical properties of some widely used fluorescent proteins under two-photon excitation conditions. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 262:120133. [PMID: 34243141 DOI: 10.1016/j.saa.2021.120133] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/17/2021] [Accepted: 06/28/2021] [Indexed: 06/13/2023]
Abstract
Understanding the photophysical properties of fluorescent proteins (FPs), such as emission and absorption spectra, molecular brightness, photostability, and photo-switching, is critical to the development of criteria for their selection as tags for fluorescent-based biological applications. While two-photon excitation imaging techniques have steadily gained popularity - due to comparatively deeper penetration depth, reduced out-of-focus photobleaching, and wide separation between emission spectra and two-photon excitation spectra -, most studies reporting on the photophysical properties of FPs tend to remain focused on single-photon excitation. Here, we report our investigation of the photophysical properties of several commonly used fluorescent proteins using two-photon microscopy with spectral resolution in both excitation and emission. Our measurements indicate that not only the excitation (and sometimes emission) spectra of FPs may be markedly different between single-photon and two-photon excitation, but also their relative brightness and their photo-stability. A good understanding of the photophysical properties of FPs under two-photon excitation is essential for choosing the right tag(s) for a desired experiment.
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Affiliation(s)
- Dhruba P Adhikari
- Department of Physics, University of Wisconsin-Milwaukee, WI 53211, USA
| | - Gabriel Biener
- Department of Physics, University of Wisconsin-Milwaukee, WI 53211, USA
| | | | - Dammar N Badu
- Department of Physics, University of Wisconsin-Milwaukee, WI 53211, USA
| | - Joel D Paprocki
- Department of Physics, University of Wisconsin-Milwaukee, WI 53211, USA
| | - Annie Eis
- Department of Physics, University of Wisconsin-Milwaukee, WI 53211, USA
| | - Paul S-H Park
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Ionel Popa
- Department of Physics, University of Wisconsin-Milwaukee, WI 53211, USA
| | - Valerică Raicu
- Department of Physics, University of Wisconsin-Milwaukee, WI 53211, USA; Department of Biological Sciences, University of Wisconsin-Milwaukee, WI 53211, USA.
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4
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Out-of-Phase Imaging after Optical Modulation (OPIOM) for Multiplexed Fluorescence Imaging Under Adverse Optical Conditions. Methods Mol Biol 2021; 2350:191-227. [PMID: 34331287 DOI: 10.1007/978-1-0716-1593-5_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fluorescence imaging has become a powerful tool for observations in biology. Yet it has also encountered limitations to overcome optical interferences of ambient light, autofluorescence, and spectrally interfering fluorophores. In this account, we first examine the current approaches which address these limitations. Then we more specifically report on Out-of-Phase Imaging after Optical Modulation (OPIOM), which has proved attractive for highly selective multiplexed fluorescence imaging even under adverse optical conditions. After exposing the OPIOM principle, we detail the protocols for successful OPIOM implementation.
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Pandey S, Mukherjee D, Kshirsagar P, Patra C, Bodas D. Multiplexed bio-imaging using cadmium telluride quantum dots synthesized by mathematically derived process parameters in a continuous flow active microreactor. Mater Today Bio 2021; 11:100123. [PMID: 34458715 PMCID: PMC8379697 DOI: 10.1016/j.mtbio.2021.100123] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/15/2021] [Accepted: 07/17/2021] [Indexed: 12/14/2022] Open
Abstract
Quantum dots (QDs) are semiconductor nanocrystals with unique size-tunable emissions. To obtain a precise emission spectrum, monodispersity in size is imperative, which is achieved by controlling the reaction kinetics in a continuous flow of active microreactors. Further, a multivariate approach (dimensional analysis) is employed to impose stringent control on the reaction process resulting in monodispersed preparation of cadmium telluride (CdTe) quantum dots. Dimensional analysis knits multiple variables into a dimensionless mathematical form which not only predicts parameters precisely to obtain narrow size tunability but also guarantees reproducibility in synthesis. Analytical, structural, and optical characterization of the microreactor synthesized polydimethylsiloxane (PDMS) coated CdTe QDs reveal quantum efficient (61.5%), photostable (44%), and biocompatible nanocrystals of 5-15 nm. Further, PDMS-coated QDs (P-QDs) are conjugated with organelle-specific antibodies/biomarkers for in-vitro imaging in NIH 3T3 cells. Likewise, proliferating cell nuclear antigen (PCNA) and anti-myosin (MF20), cardiomyocytes antibodies are conjugated with P-QDs (red and green, respectively) to image the zebrafish's cardiac tissue. Antibodies tagged with quantum dots are imaged simultaneously using confocal microscopy. Thus, multiplexed bio-imaging of in-vitro and zebrafish tissue is demonstrated successfully. The results indicate the suitability of continuous flow active microreactor in conjunction with the mathematical prediction of process parameters to synthesize reproducibly monodispersed and quantum efficient QDs.
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Affiliation(s)
- S. Pandey
- Nanobioscience Group, Agharkar Research Institute, GG Agarkar Road, Pune, 411 004, India
- Savitribai Phule Pune University, Ganeshkhind Road, Pune, 411 007, India
| | - D. Mukherjee
- Developmental Biology Group, Agharkar Research Institute, GG Agarkar Road, Pune, 411 004, India
| | - P. Kshirsagar
- Bioenergy Group, Agharkar Research Institute, GG Agarkar Road, Pune, 411 004, India
| | - C. Patra
- Savitribai Phule Pune University, Ganeshkhind Road, Pune, 411 007, India
- Developmental Biology Group, Agharkar Research Institute, GG Agarkar Road, Pune, 411 004, India
| | - D. Bodas
- Nanobioscience Group, Agharkar Research Institute, GG Agarkar Road, Pune, 411 004, India
- Savitribai Phule Pune University, Ganeshkhind Road, Pune, 411 007, India
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6
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Kumar Singh A, Burkhow SJ, Wijesooriya C, Boote BW, Petrich JW, Smith EA. Inorganic Semiconductor Quantum Dots as a Saturated Excitation (SAX) Probe for Sub‐Diffraction Imaging. CHEMPHOTOCHEM 2020. [DOI: 10.1002/cptc.202000195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Avinash Kumar Singh
- Chemical and Biological Science Division The Ames laboratory US DOE 311 Iowa State University Ames IA 50011 USA
| | - Sadie J. Burkhow
- Chemical and Biological Science Division The Ames laboratory US DOE 311 Iowa State University Ames IA 50011 USA
- Department of Chemistry Iowa State University Ames IA 50011 USA
| | | | - Brett W. Boote
- Chemical and Biological Science Division The Ames laboratory US DOE 311 Iowa State University Ames IA 50011 USA
- Department of Chemistry Iowa State University Ames IA 50011 USA
| | - Jacob W. Petrich
- Chemical and Biological Science Division The Ames laboratory US DOE 311 Iowa State University Ames IA 50011 USA
- Department of Chemistry Iowa State University Ames IA 50011 USA
| | - Emily A. Smith
- Chemical and Biological Science Division The Ames laboratory US DOE 311 Iowa State University Ames IA 50011 USA
- Department of Chemistry Iowa State University Ames IA 50011 USA
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Spectral-Time Multiplexing in FRET Complexes of AgInS 2/ZnS Quantum Dot and Organic Dyes. NANOMATERIALS 2020; 10:nano10081569. [PMID: 32785050 PMCID: PMC7466523 DOI: 10.3390/nano10081569] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 07/30/2020] [Accepted: 08/03/2020] [Indexed: 12/19/2022]
Abstract
Nowadays, multiplex analysis is very popular, since it allows to detect a large number of biomarkers simultaneously. Traditional multiplex analysis is usually based on changes of photoluminescence (PL) intensity and/or PL band spectral positions in the presence of analytes. Using PL lifetime as an additional parameter might increase the efficiency of multiplex methods. Quantum dots (QDs) can be used as luminescent markers for multiplex analysis. Ternary in-based QDs are a great alternative to the traditional Cd-based one. Ternary QDs possess all advantages of traditional QDs, including tunable photoluminescence in visible range. At the same time ternary QDs do not have Cd-toxicity, and moreover they possess long spectral dependent lifetimes. This allows the use of ternary QDs as a donor for time-resolved multiplex sensing based on Förster resonance energy transfer (FRET). In the present work, we implemented FRET from AgInS2/ZnS ternary QDs to cyanine dyes absorbing in different spectral regions of QD luminescence with different lifetimes. As the result, FRET-induced luminescence of dyes differed not only in wavelengths but also in lifetimes of luminescence, which can be used for time-resolved multiplex analysis in biology and medicine.
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8
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Cao Z, Lv B, Zhang H, Lv Y, Zhang C, Zhou Y, Wang X, Xiao M. Two-photon excited photoluminescence of single perovskite nanocrystals. J Chem Phys 2019; 151:154201. [PMID: 31640389 DOI: 10.1063/1.5124734] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Lead-halide perovskite nanocrystals (NCs) have emerged as a novel type of semiconductor nanostructure, attracting great research interests in both fundamental science and practical applications. Here, we compare the optical properties of single CsPbI3 NCs under both one-photon and two-photon excitations, mainly including the photoluminescence (PL) blinking and PL decay dynamics. By means of the PL saturation effect caused by multi-exciton Auger recombination, we have also estimated a two-photon absorption cross section of ∼6.8 × 106 GM for single CsPbI3 NCs. The ability to realize efficient two-photon excitation of single perovskite NCs with strongly suppressed background fluorescence will help not only to promote their bio-imaging and biolabeling applications but also to reveal and manipulate their delicate electronic structures for potential usage in quantum information processing.
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Affiliation(s)
- Zengle Cao
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Bihu Lv
- Research Center for Smart Sensing, Zhejiang Lab, Hangzhou 311121, China
| | - Huichao Zhang
- College of Electronics and Information, Hangzhou Dianzi University, Xiasha Campus, Hangzhou 310018, China
| | - Yan Lv
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Chunfeng Zhang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Yong Zhou
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Xiaoyong Wang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Min Xiao
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
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Rodríguez-Rodríguez H, Acebrón M, Iborra FJ, Arias-Gonzalez JR, Juárez BH. Photoluminescence Activation of Organic Dyes via Optically Trapped Quantum Dots. ACS NANO 2019; 13:7223-7230. [PMID: 31194513 DOI: 10.1021/acsnano.9b02835] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Laser tweezers afford quantum dot (QD) manipulation for use as localized emitters. Here, we demonstrate fluorescence by radiative energy transfer from optically trapped colloidal QDs (donors) to fluorescent dyes (acceptors). To this end, we synthesized silica-coated QDs of different compositions and triggered their luminescence by simultaneous trapping and two-photon excitation in a microfluidic chamber filled with dyes. This strategy produces a near-field light source with great spatial maneuverability, which can be exploited to scan nanostructures. In this regard, we demonstrate induced photoluminescence of dye-labeled cells via optically trapped silica-coated colloidal QDs placed at their vicinity. Allocating nanoscale donors at controlled distances from a cell is an attractive concept in fluorescence microscopy because it dramatically reduces the number of excited dyes, which improves resolution by preventing interferences from the whole sample, while prolonging dye luminescence lifetime due to the lower power absorbed from the QDs.
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Affiliation(s)
- Héctor Rodríguez-Rodríguez
- IMDEA Nanoscience , Faraday 9, Campus de Cantoblanco, 28049 Madrid , Spain
- Department of Applied Physical Chemistry , Universidad Autónoma de Madrid , Cantoblanco, 28049 Madrid , Spain
| | - María Acebrón
- IMDEA Nanoscience , Faraday 9, Campus de Cantoblanco, 28049 Madrid , Spain
| | - Francisco J Iborra
- National Center for Biotechnology (CNB-CSIC) , Campus de Cantoblanco, 28049 Madrid , Spain
| | | | - Beatriz H Juárez
- IMDEA Nanoscience , Faraday 9, Campus de Cantoblanco, 28049 Madrid , Spain
- Department of Applied Physical Chemistry , Universidad Autónoma de Madrid , Cantoblanco, 28049 Madrid , Spain
- Condensed Matter Physics Center (IFIMAC) , Universidad Autónoma de Madrid , 28049 Madrid , Spain
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Fathi P, Khamo JS, Huang X, Srivastava I, Esch MB, Zhang K, Pan D. Bulk-state and single-particle imaging are central to understanding carbon dot photo-physics and elucidating the effects of precursor composition and reaction temperature. CARBON 2019; 145:10.1016/j.carbon.2018.12.105. [PMID: 34795455 PMCID: PMC8596966 DOI: 10.1016/j.carbon.2018.12.105] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Carbon dots have garnered attention for their strong multi-color luminescence properties and unprecedented biocompatibility. Despite significant progress in the recent past, a fundamental understanding of their photoluminescence and structure-properties relationships, especially at the bulk vs. single-particle level, has not been well established. Here we present a comparative study of bulk- and single-particle properties as a function of precursor composition and reaction temperature. The synthesis and characterization of multicolored inherently functionalized carbon dots were achieved from a variety of carbon sources, and at synthesis temperatures of 150 °C and 200 °C. Solvothermal synthesis at 200 °C led to quantum yields as high as 86%, smaller particle sizes, and a narrowed fluorescence emission, while synthesis at 150 °C resulted in a greater UV-visible absorbance, increase in nanoparticle stability, red-shifted fluorescence, and a greater resistance to bulk photobleaching. These results suggest the potential for synthesis temperature to be utilized as a simple tool for modulating carbon dot photophysical properties. Single-particle imaging resolved that particle brightness was determined by both the instantaneous intensity and the on-time duty cycle. Increasing the synthesis temperature caused an enhancement in blinking frequency, which led to an increase in on-time duty cycle in three out of four precursors.
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Affiliation(s)
- Parinaz Fathi
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL, 61801, USA
- Biomedical Technologies Group, Microsystems and Nanotechnology Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - John S. Khamo
- Department of Biochemistry, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Xuedong Huang
- Department of Chemistry, Fudan University, Shanghai, PR China
| | - Indrajit Srivastava
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL, 61801, USA
| | - Mandy B. Esch
- Biomedical Technologies Group, Microsystems and Nanotechnology Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Kai Zhang
- Department of Biochemistry, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Dipanjan Pan
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL, 61801, USA
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Rakovich A, Rakovich T. Semiconductorversusgraphene quantum dots as fluorescent probes for cancer diagnosis and therapy applications. J Mater Chem B 2018; 6:2690-2712. [DOI: 10.1039/c8tb00153g] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
This review provides a comparison of optical, chemical and biocompatibility properties of graphene and semiconductor quantum dots as fluorescent probes.
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Affiliation(s)
- Aliaksandra Rakovich
- Photonics and Nanotechnology Group
- Department of Physics
- King's College London
- London
- UK
| | - Tatsiana Rakovich
- Department of Molecular Rheumatology
- Trinity Biomedical Sciences Institute
- Dublin 2
- Ireland
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12
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Han Y, Noor MO, Sedighi A, Uddayasankar U, Doughan S, Krull UJ. Inorganic Nanoparticles as Donors in Resonance Energy Transfer for Solid-Phase Bioassays and Biosensors. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:12839-12858. [PMID: 28759726 DOI: 10.1021/acs.langmuir.7b01483] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Bioassays for the rapid detection and quantification of specific nucleic acids, proteins, and peptides are fundamental tools in many clinical settings. Traditional optical emission methods have focused on the use of molecular dyes as labels to track selective binding interactions and as probes that are sensitive to environmental changes. Such dyes can offer good detection limits based on brightness but typically have broad emission bands and suffer from time-dependent photobleaching. Inorganic nanoparticles such as quantum dots and upconversion nanoparticles are photostable over prolonged exposure to excitation radiation and tend to offer narrow emission bands, providing a greater opportunity for multiwavelength multiplexing. Importantly, in contrast to molecular dyes, nanoparticles offer substantial surface area and can serve as platforms to carry a large number of conjugated molecules. The surface chemistry of inorganic nanoparticles offers both challenges and opportunities for the control of solubility and functionality for selective molecular interactions by the assembly of coatings through coordination chemistry. This report reviews advances in the compositional design and methods of conjugation of inorganic quantum dots and upconversion nanoparticles and the assembly of combinations of nanoparticles to achieve energy exchange. Our interest is the exploration of configurations where the modified nanoparticles can be immobilized to solid substrates for the development of bioassays and biosensors that operate by resonance energy transfer (RET).
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Affiliation(s)
- Yi Han
- Chemical Sensors Group, Department of Chemical and Physical Sciences, University of Toronto Mississauga , Mississauga, Ontario, Canada L5L 1C6
| | - M Omair Noor
- Chemical Sensors Group, Department of Chemical and Physical Sciences, University of Toronto Mississauga , Mississauga, Ontario, Canada L5L 1C6
| | - Abootaleb Sedighi
- Chemical Sensors Group, Department of Chemical and Physical Sciences, University of Toronto Mississauga , Mississauga, Ontario, Canada L5L 1C6
| | - Uvaraj Uddayasankar
- Chemical Sensors Group, Department of Chemical and Physical Sciences, University of Toronto Mississauga , Mississauga, Ontario, Canada L5L 1C6
| | - Samer Doughan
- Chemical Sensors Group, Department of Chemical and Physical Sciences, University of Toronto Mississauga , Mississauga, Ontario, Canada L5L 1C6
| | - Ulrich J Krull
- Chemical Sensors Group, Department of Chemical and Physical Sciences, University of Toronto Mississauga , Mississauga, Ontario, Canada L5L 1C6
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Lyons TY, Williams DN, Rosenzweig Z. Addition of Fluorescence Lifetime Spectroscopy to the Tool Kit Used to Study the Formation and Degradation of Luminescent Quantum Dots in Solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3018-3027. [PMID: 28245133 PMCID: PMC6419519 DOI: 10.1021/acs.langmuir.6b04400] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The increasing commercialization of consumer electronic products that make use of II-VI semiconductor quantum dots (QDs) has raised significant concerns about their impact on natural systems and human health once they are released into the environment at the end of the product's lifetime. In this paper, we demonstrate the addition of fluorescence lifetime spectroscopy to the existing tool kit of spectroscopic techniques to quantitatively monitor changes in QD properties as they form and degrade in solution. Our study reveals that because of its rich information content, fluorescence lifetime spectroscopy has a limited utility as a stand-alone technique in the study of QD formation and degradation. However, combining fluorescence lifetime spectroscopy with the commonly used emission quantum yield and peak width measurements along with other analytical methods, including ultraviolet-visible spectroscopy, transmission electron microscopy, and inductively coupled plasma mass spectrometry measurements, significantly enhances the existing analytical tool kit and provides the capability to monitor in real time, the formation and degradation of luminescent QDs in organic and aqueous solutions under environmentally relevant conditions.
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Affiliation(s)
- Taeyjuana Y. Lyons
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, United States
| | - Denise N. Williams
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, United States
| | - Zeev Rosenzweig
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, United States
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14
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Demchenko AP, Dekaliuk MO. The origin of emissive states of carbon nanoparticles derived from ensemble-averaged and single-molecular studies. NANOSCALE 2016; 8:14057-14069. [PMID: 27399599 DOI: 10.1039/c6nr02669a] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
At present, there is no consensus understanding on the origin of photoluminescence of carbon nanoparticles, particularly the so-called carbon dots. Providing comparative analysis of spectroscopic studies in solution and on a single-molecular level, we demonstrate that these particles behave collectively as fixed single dipoles and probably are the quantum emitter entities. Their spectral and lifetime heterogeneity in solutions is explained by variation of the local chemical environment within and around luminescence centers. Hence, the carbon dots possess a unique hybrid combination of fluorescence properties peculiar to dye molecules, their conjugates and semiconductor nanocrystals. It is proposed that their optical properties are due to generation of H-aggregate-type excitonic states with their coherence spreading over the whole nanoparticles.
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Affiliation(s)
- Alexander P Demchenko
- A. V. Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Leontovicha street 9, Kiev, 01601, Ukraine.
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15
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Wang Y, Jiang X. Synthesis of cell-penetrated nitrogen-doped carbon dots by hydrothermal treatment of eggplant sepals. Sci China Chem 2016. [DOI: 10.1007/s11426-016-0022-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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16
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Li J, Kwok KC, Cheung NH. Determination of the Dipole Geometry of Fluorescent Nanoparticles Using Polarized Excitation and Emission Analysis. APPLIED SPECTROSCOPY 2016; 70:302-311. [PMID: 26903565 DOI: 10.1177/0003702815620542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 06/29/2015] [Indexed: 06/05/2023]
Abstract
We demonstrate that the geometries of the absorption dipole μab and emission dipole μem of nano-emitters such as quantum dots can be determined simultaneously by far-field polarimetry. The method involves plotting the emission polarization ratio against the absorption polarization ratio of single nano-emitters. Using Monte Carlo simulation, we show that these plots depend sensitively on the aspect ratio of the dipole shape. For example, the so-called 3D-2D dipole combination, that is, μab of radius ratio 1:1:1 and μem of ratio 1:1:0, would give rise to a vertical line plot. Polarization ratios of commercial cadmium selenide/zinc sulfide (CdSe/ZnS) quantum dots are measured and plotted. The empirical data points are best-fitted to yield μab of radius ratio 1:1:0.28 and μem of ratio 1:1:0.
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Affiliation(s)
- Jianan Li
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ka-Cheung Kwok
- Department of Physics, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Nai-Ho Cheung
- Department of Physics, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
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17
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18
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Wegner KD, Hildebrandt N. Quantum dots: bright and versatile in vitro and in vivo fluorescence imaging biosensors. Chem Soc Rev 2015; 44:4792-4834. [DOI: 10.1039/c4cs00532e] [Citation(s) in RCA: 562] [Impact Index Per Article: 62.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Colourful cells and tissues: semiconductor quantum dots and their versatile applications in multiplexed bioimaging research.
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Affiliation(s)
- K. David Wegner
- NanoBioPhotonics
- Institut d'Electronique Fondamentale
- Université Paris-Sud
- 91405 Orsay Cedex
- France
| | - Niko Hildebrandt
- NanoBioPhotonics
- Institut d'Electronique Fondamentale
- Université Paris-Sud
- 91405 Orsay Cedex
- France
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19
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Shi J, Tian F, Lyu J, Yang M. Nanoparticle based fluorescence resonance energy transfer (FRET) for biosensing applications. J Mater Chem B 2015; 3:6989-7005. [DOI: 10.1039/c5tb00885a] [Citation(s) in RCA: 171] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Nanoparticle based FRET assays have higher energy transfer efficiency and better performance compared with traditional organic fluorophore based FRET assays.
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Affiliation(s)
- Jingyu Shi
- Interdisciplinary Division of Biomedical Engineering
- the Hong Kong Polytechnic University
- Kowloon
- P. R. China
| | - Feng Tian
- Interdisciplinary Division of Biomedical Engineering
- the Hong Kong Polytechnic University
- Kowloon
- P. R. China
| | - Jing Lyu
- Interdisciplinary Division of Biomedical Engineering
- the Hong Kong Polytechnic University
- Kowloon
- P. R. China
| | - Mo Yang
- Interdisciplinary Division of Biomedical Engineering
- the Hong Kong Polytechnic University
- Kowloon
- P. R. China
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20
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Yaghini E, Giuntini F, Eggleston IM, Suhling K, Seifalian AM, MacRobert AJ. Fluorescence lifetime imaging and FRET-induced intracellular redistribution of Tat-conjugated quantum dot nanoparticles through interaction with a phthalocyanine photosensitiser. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:782-792. [PMID: 24031023 DOI: 10.1002/smll.201301459] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 07/02/2013] [Indexed: 06/02/2023]
Abstract
The interaction of Tat-conjugated PEGylated CdSe/ZnS quantum dots (QD) with the amphiphilic disulfonated aluminium phthalocyanine photosensitiser is investigated in aqueous solution and in a human breast cancer cell line. In aqueous solution, the QDs and phthalocyanine form stable nanocomposites. Using steady-state and time-resolved fluorescence measurements combined with singlet oxygen detection, efficient Förster resonance energy transfer (FRET) is observed with the QDs acting as donors, and the phthalocyanine photosensitiser, which mediates production of singlet oxygen, as acceptors. In cells, the Tat-conjugated QDs localise in lysosomes and the QD fluorescence lifetimes are close to values observed in aqueous solution. Strong FRET-induced quenching of the QD lifetime is observed in cells incubated with the nanocomposites using fluorescence lifetime imaging microscopy (FLIM). Using excitation of the QDs at wavelengths where phthalocyanine absorption is negligible, FRET-induced release of QDs from endo/lysosomes is confirmed using confocal imaging and FLIM, which is attributed to photooxidative damage to the endo/lysosomal membranes mediated by the phthalocyanine acceptor.
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Affiliation(s)
- Elnaz Yaghini
- National Medical Laser Centre, Division of Surgery & Interventional Science and UCL Institute for Biomedical Engineering, University College London, London, UK
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21
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Fei X, Zhang Y, Zhu S, Liu L, Yu L. Spectral study and protein labeling of inclusion complex between dye and calixarene sulfonate. APPLIED SPECTROSCOPY 2013; 67:520-525. [PMID: 23643041 DOI: 10.1366/12-06856] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The host-guest inclusion complex of calix[6]arene sulfonate (SCA6) with thiazole orange (TO) formed in aqueous solution was studied. Absorption and fluorescence techniques were used for the analysis of this inclusion complex. The addition of calixarene sulfonate leads to a decrease in both absorption and fluorescence intensity of the dye, indicating that the inclusion complex was formed. Simultaneously, the inclusion phenomenon of another cyanine dye, Cy3, with calixarene sulfonate was investigated. The stability constant of the two complexes was determined, and the results were compared. The water solubility of TO dye was increased in the presence of calixarene sulfonate, and further protein labeling experiments suggested that this TO-SCA6 complex can act as a fluorescent probe for labeling of biomolecules.
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Affiliation(s)
- Xuening Fei
- Department of Chemistry, School of Science, Tianjin Institute of Urban Construction, 300384, Tianjin, China
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22
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Wu HF, Gopal J, Abdelhamid HN, Hasan N. Quantum dot applications endowing novelty to analytical proteomics. Proteomics 2013; 12:2949-61. [PMID: 22930415 DOI: 10.1002/pmic.201200295] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This review surveys all the state-of-art applications of quantum dots (QDs) in conventional and modern analytical methods in proteomic studies. A brief introduction of QDs and their properties is initially presented followed by outlining the application of QDs in fluorescence, MS, imaging, and cancer-based proteomics. The in-depth application of QDs in MALDI-MS and surface assisted laser desorption/ionization-MS has been elaborately discussed, summarizing the speculated mechanism behind the protein-QDs interactions during QD matrix applications leading to enhanced detection sensitivity.
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Affiliation(s)
- Hui-Fen Wu
- Department of Chemistry, National Sun Yat Sen University, Kaohsiung, Taiwan.
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23
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Menéndez GO, Pichel ME, Spagnuolo CC, Jares-Erijman EA. NIR fluorescent biotinylated cyanine dye: optical properties and combination with quantum dots as a potential sensing device. Photochem Photobiol Sci 2012; 12:236-40. [PMID: 22972309 DOI: 10.1039/c2pp25174d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a water soluble and fluorescent biotinylated probe derived from a carbocyanine dye. A high efficiency of energy transfer was measured when the dyes were placed on the surface of streptavidin conjugated quantum dots. The system is a model platform for potential application as a FRET-based fluorescent sensor.
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Affiliation(s)
- Guillermo O Menéndez
- Dpto. de Química Orgánica, CIHIDECAR-CONICET, Fac. Cs. Exactas y Nat., Universidad de Buenos Aires Int., Güiraldes 2160, Pabellón II, Cdad. Universitaria (1428), Cdad. Autónoma de Buenos Aires, Argentina
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24
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Haro-González P, Martínez-Maestro L, Martín IR, García-Solé J, Jaque D. High-sensitivity fluorescence lifetime thermal sensing based on CdTe quantum dots. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:2652-8. [PMID: 22700354 DOI: 10.1002/smll.201102736] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Revised: 04/16/2012] [Indexed: 05/23/2023]
Abstract
The potential use of CdTe quantum dots as luminescence nano-probes for lifetime fluorescence nano-thermometry is demonstrated. The maximum thermal sensitivity achievable is strongly dependent on the quantum dot size. For the smallest sizes (close to 1 nm) the lifetime thermal sensitivity overcomes those of conventional nano-probes used in fluorescence lifetime thermometry.
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Affiliation(s)
- P Haro-González
- Departamento de Física Fundamental y Experimental, Electrónica y Sistemas, Universidad de La Laguna, Tenerife, Spain
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25
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Critical Role of Amyloid-like Oligomers of Drosophila Orb2 in the Persistence of Memory. Cell 2012; 148:515-29. [DOI: 10.1016/j.cell.2012.01.004] [Citation(s) in RCA: 220] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 09/23/2011] [Accepted: 11/28/2011] [Indexed: 01/22/2023]
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26
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Thiry M, Boldt K, Nikolic MS, Schulz F, Ijeh M, Panicker A, Vossmeyer T, Weller H. Fluorescence properties of hydrophilic semiconductor nanoparticles with tridentate polyethylene oxide ligands. ACS NANO 2011; 5:4965-4973. [PMID: 21619021 DOI: 10.1021/nn201065y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this contribution a facile, one-step synthesis of tridentate thiol-functionalized PEO ligands and their ability to stabilize CdSe/CdS/ZnS core-shell-shell nanoparticles in aqueous media are described. The PEO-coated quantum dots show colloidal stability as well as preserved fluorescence even at very low concentrations of a few nM. For improved ligand attachment and enhanced fluorescence properties a method for ligand exchange was developed, which includes formation of a ligand zinc complex before the actual exchange reaction. The stability and fluorescence properties in various aqueous buffers and cell media and at pH values down to pH 3 were investigated. The firm binding of the tridentate ligands to the particle surface makes this ligand-particle system a promising tool for biological applications. In addition, activation of the ligands' terminal hydroxyl group for covalent biofunctionalization by esterification with succinic acid is reported.
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Affiliation(s)
- Marc Thiry
- Institute for Physical Chemistry, University of Hamburg, Grindelallee 177, 20146 Hamburg, Germany
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27
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Díaz SA, Menéndez GO, Etchehon MH, Giordano L, Jovin TM, Jares-Erijman EA. Photoswitchable water-soluble quantum dots: pcFRET based on amphiphilic photochromic polymer coating. ACS NANO 2011; 5:2795-2805. [PMID: 21375335 DOI: 10.1021/nn103243c] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A novel surface architecture was developed to generate biocompatible and stable photoswitchable quantum dots (psQDs). Photochromic diheteroarylethenes, which undergo thermally stable photoconversions between two forms with different spectral properties in organic solvents, were covalently linked to an amphiphilic polymer that self-assembles with the lipophilic chains surrounding commercial hydrophobic core-shell CdSe/ZnS QDs. This strategy creates a small (∼7 nm diameter) nanoparticle (NP) that is soluble in aqueous medium. The NP retains and even enhances the desirable properties of the original QD (broad excitation, narrow emission, photostability), but the brightness of its emission can be tailored by light. The modulation of emission monitored by steady-state and time-resolved fluorescence was 35-40%. The psQDs exhibit unprecedented photostability and fatigue resistance over at least 16 cycles of photoconversion.
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Affiliation(s)
- Sebastián A Díaz
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, CIHIDECAR, CONICET, 1428 Buenos Aires, Argentina
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28
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Abstract
Ligand binding to cell membrane receptors sets off a series of protein interactions that convey the nuances of ligand identity to the cell interior. The information may be encoded in conformational changes, the interaction kinetics and, in the case of multichain immunoreceptors, by chain rearrangements. The signals may be modulated by dynamic compartmentalization of the cell membrane, cellular architecture, motility, and activation-all of which are difficult to reconstitute for studies of receptor signaling in vitro. In this paper, we will discuss how protein interactions in general and receptor signaling in particular can be studied in living cells by different fluorescence imaging techniques. Particularly versatile are methods that exploit Förster resonance energy transfer (FRET), which is exquisitely sensitive to the nanometer-range proximity and orientation between fluorophores. Fluorescence correlation microscopy (FCM) can provide complementary information about the stoichiometry and diffusion kinetics of large complexes, while bimolecular fluorescence complementation (BiFC) and other complementation techniques can capture transient interactions. A continuing challenge is extracting from the imaging data the quantitative information that is necessary to verify different models of signal transduction.
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Affiliation(s)
- Tomasz Zal
- Department of Immunology, University of Texas, MD Anderson Cancer Center, Houston TX, USA
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29
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Dorokhin D, Hsu SH, Tomczak N, Blum C, Subramaniam V, Huskens J, Reinhoudt DN, Velders AH, Vancso GJ. Visualizing resonance energy transfer in supramolecular surface patterns of β-CD-functionalized quantum dot hosts and organic dye guests by fluorescence lifetime imaging. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2010; 6:2870-2876. [PMID: 21080386 DOI: 10.1002/smll.201000713] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Detection of an analyte via supramolecular host-guest binding and quantum dot (QD)-based fluorescence resonance energy transfer (FRET) signal transduction mechanism is demonstrated. Surface patterns consisting of CdSe/ZnS QDs functionalized at their periphery with β-cyclodextrin (β-CD) were obtained by immobilization of the QDs from solution onto glass substrates patterned with adamantyl-terminated poly(propylene imine) dendrimeric "glue." Subsequent formation of host-guest complexes between vacant β-CD on the QD surface and an adamantyl-functionalized lissamine rhodamine resulting in FRET was confirmed by fluorescence microscopy, spectroscopy, and fluorescence lifetime imaging microscopy (FLIM).
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Affiliation(s)
- Denis Dorokhin
- Materials Science and Technology of Polymers, Faculty of Science and Technology and MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
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30
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Teng X, Pu H, Möhwald H, Sui J. Hydrophobic iron oxide and CdSe/ZnS nanocrystal loaded polyglutamate/polyelectrolyte micro- and nanocapsules. NANOSCALE 2010; 2:2150-2159. [PMID: 20714649 DOI: 10.1039/c0nr00232a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A novel, simple and generic method for the preparation of hydrophobic nanocrystal loaded composite capsules is introduced. Firstly, magnetic Fe(3)O(4) nanocrystals prepared by pyrolysis of fatty acid iron salts in non-aqueous media were successfully incorporated into water-dispersible polyglutamate/polyelectrolyte capsules by combining an ultrasonic protocol and polyelectrolyte layer-by-layer (LBL) assembly. Then, inspired by the similar synthesis mechanism of oxide and semiconductor nanocrystals based on organometallic approaches in non-aqueous media, two kinds of fluorescent semiconductor quantum dots (zinc sulfide-capped cadmium selenide nanocrystals) were chosen as models to explore QD loaded composite capsules. With rhodamine B isothiocyanate (RBITC) tagging PEI as outer layers, fluorescence micrographs and confocal microscopy images indicate that CdSe/ZnS QDs were successfully incorporated into polyglutamate/polyelectrolyte capsules with almost unchanged optical properties and the color of RBITC tagging PEI shell can be changed under different excitation. Color transformation ascribed to spectral conversion of embedded QDs was also observed after the capsules were stored under day light for days. TEM, electron diffraction (ED), and ESEM revealed that the method leads to well-defined nanocrystal loaded composite nanocapsules and is simple and generic.
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Affiliation(s)
- Xinrong Teng
- School of Materials Science and Engineering, Tongji University, 4800 Cao An Rd, Jiading District, 201804 Shanghai, China.
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31
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Howes P, Green M, Levitt J, Suhling K, Hughes M. Phospholipid encapsulated semiconducting polymer nanoparticles: their use in cell imaging and protein attachment. J Am Chem Soc 2010; 132:3989-96. [PMID: 20175539 DOI: 10.1021/ja1002179] [Citation(s) in RCA: 188] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Semiconducting polymer nanospheres (SPNs) have been synthesized and encapsulated in phospholipid micelles by a solvent evaporation technique. Four different conjugated polymers were used, yielding aqueous dispersions of nanoparticles which emit across the visible spectrum. The synthesis was simple and easily reproducible, and the resultant nanoparticle solutions exhibited high colloidal stability. As these encapsulated SPNs do not contain any toxic materials and show favorable optical properties, they appear to be a promising imaging agent in biomedical and imaging applications. The SPNs were used in simple fluorescence imaging experiments and showed uptake in SH-SY5Y neuroblastoma and live HeLa cells. Carboxylic acid functionalized SPNs were also synthesized and conjugated to bovine serum albumin (BSA) by carbodiimide-mediated chemistry, a key step in the realization of targeted imaging using conjugated polymers.
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Affiliation(s)
- Philip Howes
- Department of Physics, King's College London, Strand, London WC2R 2LS, UK
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32
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Deng C, Li J, Ma W. Detection of FRET efficiency in imaging systems by photo-bleaching acceptors. Talanta 2010; 82:771-4. [DOI: 10.1016/j.talanta.2010.05.051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Revised: 05/18/2010] [Accepted: 05/22/2010] [Indexed: 12/01/2022]
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Affiliation(s)
- Mikhail Y. Berezin
- Department of Radiology, Washington University School of Medicine, 4525 Scott Ave, St. Louis, USA, Tel. 314-747-0701, 314-362-8599, fax 314-747-5191
| | - Samuel Achilefu
- Department of Radiology, Washington University School of Medicine, 4525 Scott Ave, St. Louis, USA, Tel. 314-747-0701, 314-362-8599, fax 314-747-5191
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34
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Resch-Genger U, Grabolle M, Nitschke R, Nann T. Nanocrystals and Nanoparticles Versus Molecular Fluorescent Labels as Reporters for Bioanalysis and the Life Sciences: A Critical Comparison. ADVANCED FLUORESCENCE REPORTERS IN CHEMISTRY AND BIOLOGY II 2010. [DOI: 10.1007/978-3-642-04701-5_1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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35
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Giraud G, Schulze H, Bachmann TT, Campbell CJ, Mount AR, Ghazal P, Khondoker MR, Ember SW, Ciani I, Tlili C, Walton AJ, Terry JG, Crain J. Solution state hybridization detection using time-resolved fluorescence anisotropy of quantum dot-DNA bioconjugates. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2009.11.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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36
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May A, Bhaumik S, Gambhir SS, Zhan C, Yazdanfar S. Whole-body, real-time preclinical imaging of quantum dot fluorescence with time-gated detection. JOURNAL OF BIOMEDICAL OPTICS 2009; 14:060504. [PMID: 20059235 PMCID: PMC2801727 DOI: 10.1117/1.3269675] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We describe a wide-field preclinical imaging system optimized for time-gated detection of quantum dot fluorescence emission. As compared to continuous wave measurements, image contrast was substantially improved by suppression of short-lifetime background autofluorescence. Real-time (8 frames/s) biological imaging of subcutaneous quantum dot injections is demonstrated simultaneously in multiple living mice.
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37
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Lidke DS, Wilson BS. Caught in the act: quantifying protein behaviour in living cells. Trends Cell Biol 2009; 19:566-74. [PMID: 19801189 DOI: 10.1016/j.tcb.2009.08.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 08/14/2009] [Accepted: 08/20/2009] [Indexed: 01/23/2023]
Abstract
Protein localization and dynamics both have important roles in cell signal transduction. Biochemical studies have elucidated many details about the chain of events in signal cascades, but the poor temporal resolution and absence of spatial localization in these conventional techniques make it difficult to determine the "where and when" of protein interactions. Over the past decade, imaging technologies and biological tools have developed to a point where many fundamental questions about protein activity can be addressed at the molecular level in living cells, revealing spatio-temporal information that is not provided by traditional biochemical assays. In this review, we illustrate the power of emerging fluorescence microscopy techniques to capture and quantify protein dynamics.
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Affiliation(s)
- Diane S Lidke
- Department of Pathology and Cancer Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
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38
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Wang Q, Chen B, Liu P, Zheng M, Wang Y, Cui S, Sun D, Fang X, Liu CM, Lucas WJ, Lin J. Calmodulin binds to extracellular sites on the plasma membrane of plant cells and elicits a rise in intracellular calcium concentration. J Biol Chem 2009; 284:12000-7. [PMID: 19254956 PMCID: PMC2673269 DOI: 10.1074/jbc.m808028200] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 12/31/2008] [Indexed: 11/06/2022] Open
Abstract
Calmodulin (CaM) is a highly conserved intracellular calcium sensor. In plants, CaM also appears to be present in the apoplasm, and application of exogenous CaM has been shown to influence a number of physiological functions as a polypeptide signal; however, the existence and localization of its corresponding apoplasmic binding sites remain controversial. To identify the site(s) of action, a CaM-conjugated quantum dot (QD) system was employed for single molecule level detection at the surface of plant cells. Using this approach, we show that QD-CaM binds selectively to sites on the outer surface of the plasma membrane, which was further confirmed by high resolution transmission electron microscopy. Measurements of Ca(2+) fluxes across the plasma membrane, using ion-selective microelectrodes, demonstrated that exogenous CaM induces a net influx into protoplasts. Consistent with these flux studies, calcium-green-dextran and FRET experiments confirmed that applied CaM/QD-CaM elicited an increase in cytoplasmic Ca(2+) levels. These results support the hypothesis that apoplasmic CaM can act as a signaling agent. These findings are discussed in terms of CaM acting as an apoplasmic peptide ligand to mediate transmembrane signaling in the plant kingdom.
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Affiliation(s)
- Qinli Wang
- Key Laboratory of Photosynthesis and Molecular Environment Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
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39
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Fluorescence lifetime imaging of quantum dot labeled DNA microarrays. Int J Mol Sci 2009; 10:1930-1941. [PMID: 19468347 PMCID: PMC2680655 DOI: 10.3390/ijms10041930] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Revised: 04/16/2009] [Accepted: 04/21/2009] [Indexed: 11/16/2022] Open
Abstract
Quantum dot (QD) labeling combined with fluorescence lifetime imaging microscopy is proposed as a powerful transduction technique for the detection of DNA hybridization events. Fluorescence lifetime analysis of DNA microarray spots of hybridized QD labeled target indicated a characteristic lifetime value of 18.8 ns, compared to 13.3 ns obtained for spots of free QD solution, revealing that QD labels are sensitive to the spot microenvironment. Additionally, time gated detection was shown to improve the microarray image contrast ratio by 1.8, achieving femtomolar target sensitivity. Finally, lifetime multiplexing based on Qdot525 and Alexa430 was demonstrated using a single excitation-detection readout channel.
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Rife JC, Long JP, Wilkinson J, Whitman LJ. Particle tracking single protein-functionalized quantum dot diffusion and binding at silica surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:3509-3518. [PMID: 19708242 DOI: 10.1021/la802144e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We evaluate commercial QD585 and QD605 streptavidin-functionalized quantum dots (QDs) for single-particle tracking microscopy at surfaces using total internal reflectance fluorescence and measure single QD diffusion and nonspecific binding at silica surfaces in static and flow conditions. The QD diffusion coefficient on smooth, near-ideal, highly hydroxylated silica surfaces is near bulk-solution diffusivity, as expected for repulsive surfaces, but many QD trajectories on rougher, less-than-ideal surfaces or regions display transient adsorptions. We attribute the binding to defect sites or adsorbates, possibly in conjunction with protein conformation changes, and estimate binding energies from the transient adsorption lifetimes. We also assess QD parameters relevant to tracking, including hydrodynamic radius, charge state, signal levels, blinking reduction with reducing solutions, and photoinduced blueing and bleaching.
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Affiliation(s)
- Jack C Rife
- Naval Research Laboratory, Washington, D.C. 20375, USA.
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Douma K, Prinzen L, Slaaf DW, Reutelingsperger CPM, Biessen EAL, Hackeng TM, Post MJ, van Zandvoort MAMJ. Nanoparticles for optical molecular imaging of atherosclerosis. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2009; 5:544-557. [PMID: 19226595 DOI: 10.1002/smll.200801079] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Molecular imaging contributes to future personalized medicine dedicated to the treatment of cardiovascular disease, the leading cause of mortality in industrialized countries. Endoscope-compatible optical imaging techniques would offer a stand-alone alternative and high spatial resolution validation technique to clinically accepted imaging techniques in the (intravascular) assessment of vulnerable atherosclerotic lesions, which are predisposed to initiate acute clinical events. Efficient optical visualization of molecular epitopes specific for vulnerable atherosclerotic lesions requires targeting of high-quality optical-contrast-enhancing particles. In this review, we provide an overview of both current optical nanoparticles and targeting ligands for optical molecular imaging of atherosclerotic lesions and speculate on their applicability in the clinical setting.
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Affiliation(s)
- Kim Douma
- Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands.
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Abstract
Suitable labels are at the core of Luminescence and fluorescence imaging and sensing. One of the most exciting, yet also controversial, advances in label technology is the emerging development of quantum dots (QDs)--inorganic nanocrystals with unique optical and chemical properties but complicated surface chemistry--as in vitro and in vivo fluorophores. Here we compare and evaluate the differences in physicochemical properties of common fluorescent labels, focusing on traditional organic dyes and QDs. Our aim is to provide a better understanding of the advantages and limitations of both classes of chromophores, to facilitate label choice and to address future challenges in the rational design and manipulation of QD labels.
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Sutter JU, Macmillan AM, Birch DJS, Rolinski OJ. Toward single-metal-ion sensing by Förster resonance energy transfer. Ann N Y Acad Sci 2008; 1130:62-7. [PMID: 18596333 DOI: 10.1196/annals.1430.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Here we describe progress toward our objective of detecting single nonfluorescent hydrated metal ions. Single-ion detection represents detection and spectroscopy at the ultimate sensitivity level of approximately 1.6 x 10(-24) M. Achieving this goal would provide a breakthrough in analytical science and allow much more detailed insight into sensor-ion interaction than that available with conventional bulk detection methods. We combine recent advances in confocal microscopy with the sensitivity and the noninvasive nature of fluorescence by analyzing Förster resonance energy transfer between sensor fluorophores and transition metal ions.
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Affiliation(s)
- Jens U Sutter
- Photophysics Group, Department of Physics, John Anderson Bldg., University of Strathclyde, Glasgow G4 0NG, Scotland, UK.
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Rajan SS, Liu HY, Vu TQ. Ligand-bound quantum dot probes for studying the molecular scale dynamics of receptor endocytic trafficking in live cells. ACS NANO 2008; 2:1153-1166. [PMID: 19206333 DOI: 10.1021/nn700399e] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Endocytic receptor trafficking is a complex, dynamic process underlying fundamental cell function. An integrated understanding of endocytosis at the level of single or small numbers of ligand bound-receptor complexes inside live cells is currently hampered by technical limitations. Here, we develop and test ligand nerve growth factor-bound quantum dot (NGF-QD) bioconjugates for imaging discrete receptor endocytic events inside live NGF-responsive PC12 cells. Using single particle tracking, QD hybrid gel coimmunoprecipitation, and immuno-colocalization, we illustrate and validate the use of QD-receptor complexes for imaging receptor trafficking at synchronized time points after QD-ligand-receptor binding and internalization (t = 15-150 min). The unique value of these probes is illustrated by new dynamic observations: (1) that endocytosis proceeds at strikingly regulated fashion, and (2) that diffusive and active forms of transport inside cells are rapid and efficient. QDs are powerful intracellular probes that can provide biologists with new capabilities and fresh insight for studying endocytic receptor signaling events, in real time, and at the resolution of single or small numbers of receptors in live cells.
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Affiliation(s)
- Sujata Sundara Rajan
- Department of Biomedical Engineering, Oregon Health & Science University, 3303 SW Bond Avenue, 13B, Portland, Oregon 97239, USA
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46
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Abstract
Nanotechnology offers many opportunities for enhanced diagnostic and therapeutic medicine against cancer and other diseases. In this review, the special properties that result from the nanoscale size of quantum dots, metal colloids, superparamagnetic iron oxide, and carbon-based nanostructures are reviewed and interpreted against a background of the structural and electronic detail that gives rise to their nanotechnologic behavior. The detection and treatment of cancer is emphasized, with special attention paid to the biologic targeting of the disease. The future of nanotechnology in cancer research and clinical practice is projected to focus on 'theranostic' nanoparticles that are both diagnostic and therapeutic by design.
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McGrath N, Barroso M. Quantum dots as fluorescence resonance energy transfer donors in cells. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:031210. [PMID: 18601534 DOI: 10.1117/1.2939417] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Quantum dots (QDs) promise to revolutionize the way fluorescence imaging is used in the cell biology field. The unique fluorescent spectral characteristics, high photostability, low photobleaching, and tight emission spectra of QDs position them above traditional dyes. We will address the ability of water-stabilized QDs to behave as effective fluorescence resonance energy transfer (FRET) donors in cells upon transferrin-receptor-(TFR) mediated endocytosis. Confocal microscopy detects whether donor QD transferrin conjugates transfer energy to acceptor organic fluorophore-transferrin conjugate molecules in endocytic compartments. QDs are shown to be effective FRET donors when internalized into cells via the transferring receptor-mediated endocytic pathway. Upon pairing with the appropriate acceptor dyes, QDs will reduce the laborious data processing that is required to compensate for bleed through contamination between organic dye donor and acceptor pair signals. The QD technology simplifies and expands the use of FRET in the analysis of complex cellular processes that may involve protein organization in intracellular membranes as well as protein-protein interactions.
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Affiliation(s)
- Nicole McGrath
- Albany Medical College, Center for Cardiovascular Sciences, Albany, New York 12208, USA
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Saini V, Martyshkin DV, Mirov SB, Perez A, Perkins G, Ellisman MH, Towner VD, Wu H, Pereboeva L, Borovjagin A, Curiel DT, Everts M. An adenoviral platform for selective self-assembly and targeted delivery of nanoparticles. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2008; 4:262-269. [PMID: 18200644 DOI: 10.1002/smll.200700403] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Metallic nanoparticles (NPs) can be used for the diagnosis, imaging, and therapy of tumors and cardiovascular disease. However, targeted delivery of NPs to specific cells remains a major limitation for clinical realization of these potential treatment options. Herein, a novel strategy for the specific coupling of NPs to a targeted adenoviral (Ad) platform to deliver NPs to specific cells is defined. Genetic manipulation of the gene-therapy vector is combined with a specific chemical coupling strategy. In particular, a high-affinity interaction between a sequence of six-histidine amino acid residues genetically incorporated into Ad capsid proteins and nickel(II) nitrilotriacetic acid on the surface of gold NPs is employed. The selective self-assembly of gold NPs and Ad vectors into multifunctional platforms does not negatively affect the targeting of Ad to specific cells. This opens the possibility of using Ad vectors for targeted NP delivery, thereby providing a new type of combinatorial approach for the treatment of diseases that involves both nanotechnology and gene therapy.
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Affiliation(s)
- Vaibhav Saini
- Division of Human Gene Therapy, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Hild WA, Breunig M, Goepferich A. Quantum dots – Nano-sized probes for the exploration of cellular and intracellular targeting. Eur J Pharm Biopharm 2008; 68:153-68. [PMID: 17869074 DOI: 10.1016/j.ejpb.2007.06.009] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Revised: 05/25/2007] [Accepted: 06/04/2007] [Indexed: 10/23/2022]
Abstract
Nanoparticles emerged as promising tool in drug targeting, since, after appropriate modification, they are able to deliver their payload to specific sites, like tissues, cells, or even certain cellular organelles. In this context, the delivery of nanoparticles from the circulation into the target cells represents a crucial step. Here, model drug delivery systems such as quantum dots are ideal candidates to elucidate this process in more detail, since they provide outstanding features like a small and uniform size, unique optical properties for most sensitive detection and modifiable surfaces. Recent progress in the surface chemistry of quantum dots expanded their use in biological applications, reduced their cytotoxicity and rendered quantum dots a powerful tool for the investigation of distinct cellular processes, like uptake, receptor trafficking and intracellular delivery. In this review, we will not only describe the ideal attributes of QDs for biological applications and imaging but also their distinct specific and non-specific pathways into the cells as well as their intracellular fate.
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Affiliation(s)
- W A Hild
- Department of Pharmaceutical Technology, University of Regensburg, Universitaetsstrasse 31, 93040 Regensburg, Germany
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Microcontact printing of quantum dot bioconjugate arrays for localized capture and detection of biomolecules. Biomed Microdevices 2008; 10:367-74. [DOI: 10.1007/s10544-007-9144-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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