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Seraj F, Khan KM, Iqbal J, Imran A, Hussain Z, Salar U, Hameed S, Taha M. Evaluation of synthetic aminoquinoline derivatives as urease inhibitors: in vitro, in silico and kinetic studies. Future Med Chem 2023; 15:1703-1717. [PMID: 37814798 DOI: 10.4155/fmc-2023-0168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/11/2023] Open
Abstract
Background: Quinoline and acyl thiourea scaffolds have major chemical significance in medicinal chemistry. Quinoline-based acyl thiourea derivatives may potentially target the urease enzyme. Materials & methods: Quinoline-based acyl thiourea derivatives 1-26 were synthesized and tested for urease inhibitory activity. Results: 19 derivatives (1-19) showed enhanced urease enzyme inhibitory potential (IC50 = 1.19-18.92 μM) compared with standard thiourea (IC50 = 19.53 ± 0.032 μM), whereas compounds 20-26 were inactive. Compounds with OCH3, OC2H5, Br and CH3 on the aryl ring showed significantly greater inhibitory potential than compounds with hydrocarbon chains of varying length. Molecular docking studies were conducted to investigate ligand interactions with the enzyme's active site. Conclusion: The identified hits can serve as potential leads against the drug target urease in advanced studies.
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Affiliation(s)
- Faiza Seraj
- HEJ Research Institute of Chemistry, International Center for Chemical & Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Khalid Mohammed Khan
- HEJ Research Institute of Chemistry, International Center for Chemical & Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
- Department of Clinical Pharmacy, Institute for Research & Medical Consultations, Imam Abdulrahman Bin Faisal University, PO Box 31441, Dammam, Saudi Arabia
| | - Jamshed Iqbal
- Center of Advanced Drug Research, COMSATS University Islamabad, Abbottabad, 22060, Pakistan
| | - Aqeel Imran
- Center of Advanced Drug Research, COMSATS University Islamabad, Abbottabad, 22060, Pakistan
- Department of Pharmacy, COMSATS University Islamabad, Lahore, 54000, Pakistan
| | - Zahid Hussain
- Center of Advanced Drug Research, COMSATS University Islamabad, Abbottabad, 22060, Pakistan
| | - Uzma Salar
- Dr Panjwani Center for Molecular Medicine & Drug Research, International Center for Chemical & Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Shehryar Hameed
- HEJ Research Institute of Chemistry, International Center for Chemical & Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Muhammad Taha
- Department of Clinical Pharmacy, Institute for Research & Medical Consultations, Imam Abdulrahman Bin Faisal University, PO Box 31441, Dammam, Saudi Arabia
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2
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Tsai HY, Robidillo CJT, Matharu GK, O'Connor K, Cheong IT, Ni C, Veinot JGC, Algar WR. Spectrotemporal characterization of photoluminescent silicon nanocrystals and their energy transfer to dyes. NANOSCALE 2023. [PMID: 37449921 DOI: 10.1039/d3nr02461j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Silicon nanocrystals (SiNCs) are a promising material for applications in bioanalysis and imaging. Compared to other types of semiconductor nanocrystals, the development and characterization of energy transfer (ET) configurations with SiNCs has been far more limited, resulting in an equally limited understanding of this process and its SiNC-specific nuances. Here, we present a systematic and detailed study of ET between SiNCs and dyes. A combination of spectroelectrophoresis and time-gated and time-resolved photoluminescence measurements were used to characterize the photophysical properties of ensembles of SiNCs and gain insight into how these properties varied as a function of nanocrystal size. ET between SiNC donors and a series of non-fluorescent Black Hole Quencher (BHQ) dyes and fluorescent sulfo-Cyanine 5.5 dye acceptors was evaluated in terms of spectral properties, wavelength-resolved efficiencies, trends with spectral overlap integral, and differences between two methods of BHQ association with the SiNCs. The overall results were consistent with a Förster resonance energy transfer (FRET) mechanism where the polydispersity of the SiNCs had a significant impact on the observed ET: the choice of wavelength and timing parameters were important, and ensemble measurements represented an average of heterogeneous ET behaviors. Prospective advantages and disadvantages of SiNCs as ET donors are discussed. This study serves as a foundation for the continued and optimized development of ET configurations with SiNCs.
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Affiliation(s)
- Hsin-Yun Tsai
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada, V6T 1Z1.
| | - Christopher Jay T Robidillo
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
- Department of Physical Sciences and Mathematics, University of the Philippines Manila, P. Faura Street, Ermita, Manila 1000, Philippines
| | - Gunwant K Matharu
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
| | - Kevin O'Connor
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
| | - I Teng Cheong
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
| | - Chuyi Ni
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
| | - Jonathan G C Veinot
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
| | - W Russ Algar
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada, V6T 1Z1.
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3
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Zhan X, Liu J, Zhao Y, Sun Y, Gao R, Wang H, Shi H. MOF-derived tunable spin-state MnIII doped g-C3N4 photocatalysts with enhanced photocatalytic activity. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.122146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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4
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Mathur D, Samanta A, Ancona MG, Díaz SA, Kim Y, Melinger JS, Goldman ER, Sadowski JP, Ong LL, Yin P, Medintz IL. Understanding Förster Resonance Energy Transfer in the Sheet Regime with DNA Brick-Based Dye Networks. ACS NANO 2021; 15:16452-16468. [PMID: 34609842 PMCID: PMC8823280 DOI: 10.1021/acsnano.1c05871] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Controlling excitonic energy transfer at the molecular level is a key requirement for transitioning nanophotonics research to viable devices with the main inspiration coming from biological light-harvesting antennas that collect and direct light energy with near-unity efficiency using Förster resonance energy transfer (FRET). Among putative FRET processes, point-to-plane FRET between donors and acceptors arrayed in two-dimensional sheets is predicted to be particularly efficient with a theoretical 1/r4 energy transfer distance (r) dependency versus the 1/r6 dependency seen for a single donor-acceptor interaction. However, quantitative validation has been confounded by a lack of robust experimental approaches that can rigidly place dyes in the required nanoscale arrangements. To create such assemblies, we utilize a DNA brick scaffold, referred to as a DNA block, which incorporates up to five two-dimensional planes with each displaying from 1 to 12 copies of five different donor, acceptor, or intermediary relay dyes. Nanostructure characterization along with steady-state and time-resolved spectroscopic data were combined with molecular dynamics modeling and detailed numerical simulations to compare the energy transfer efficiencies observed in the experimental DNA block assemblies to theoretical expectations. Overall, we demonstrate clear signatures of sheet regime FRET, and from this we provide a better understanding of what is needed to realize the benefits of such energy transfer in artificial dye networks along with FRET-based sensing and imaging.
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Affiliation(s)
| | | | | | - Sebastián A. Díaz
- Center for Bio/Molecular Science and Engineering Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Youngchan Kim
- Center for Materials Physics and Technology Code 6390, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Joseph S. Melinger
- Electronic Science and Technology Division Code 6800, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Ellen R. Goldman
- Center for Bio/Molecular Science and Engineering Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - John Paul Sadowski
- Center for Bio/Molecular Science and Engineering Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States; American Society for Engineering Education, Washington, D.C. 20001, United States
| | - Luvena L. Ong
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Peng Yin
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Igor L. Medintz
- Center for Bio/Molecular Science and Engineering Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
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5
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Zheng Y, Ling Y, Zhang DY, Tan CP, Zhang H, Yang GG, Wang H, Ji LN, Mao ZW. Regulating Tumor N 6 -Methyladenosine Methylation Landscape using Hypoxia-Modulating OsS x Nanoparticles. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2005086. [PMID: 33284508 DOI: 10.1002/smll.202005086] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/09/2020] [Indexed: 06/12/2023]
Abstract
The epigenetic dysregulation and hypoxia are two important factors that drive tumor malignancy, and N6 -methyladenosine (m6 A) in mRNA is involved in the regulation of gene expression. Herein, a nanocatalyst OsSx -PEG (PEG = poly(ethylene glycol)) nanoparticles (NPs) as O2 modulator is developed to improve tumor hypoxia. OsSx -PEG NPs can significantly downregulate genes involved in hypoxia pathway. Interestingly, OsSx -PEG NPs elevate RNA m6 A methylation levels to cause the m6 A-dependent mRNA degradation of the hypoxia-related genes. Moreover, OsSx -PEG NPs can regulate the expression of RNA m6 A methyltransferases and demethylases. Finally, DOX@OsSx -PEG (DOX = doxorubicin; utilized as a model drug) NPs modulate tumor hypoxia and regulate mRNA m6 A methylation of hypoxia-related genes in vivo. As the first report about relationship between catalytic nanomaterials and RNA modifications, the research opens a new avenue for unveiling the underlying action mechanisms of hypoxia-modulating nanomaterials and shows potential of regulating RNA modification to overcome chemoresistance.
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Affiliation(s)
- Yue Zheng
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Yuyi Ling
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, China
| | - Dong-Yang Zhang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Cai-Ping Tan
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Hang Zhang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Gang-Gang Yang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Hongsheng Wang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, China
| | - Liang-Nian Ji
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Zong-Wan Mao
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
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6
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Chakraborty A, Ilic S, Cai M, Gibbons BJ, Yang X, Slamowitz CC, Morris AJ. Role of Spin-Orbit Coupling in Long Range Energy Transfer in Metal-Organic Frameworks. J Am Chem Soc 2020; 142:20434-20443. [PMID: 33215496 DOI: 10.1021/jacs.0c09503] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Metal-organic frameworks (MOFs) are emerging as a promising platform for solar energy conversion applications. Their potential utilization as efficient chromophores in artificial photosynthesis is closely related to the understanding of light-harvesting and energy transfer processes that occur within these molecular scaffolds. Herein, we present the photophysical investigation of Ru(II), Ir(III), and Os(II) polypyridyl complexes incorporated into the backbone of UiO-67. In this work, we systematically study the effect of spin-orbit coupling on dipole-dipole energy transfer in MOFs using steady-state and time-resolved spectroscopic techniques. The results of our work indicate successful triplet-to-singlet energy transfer and a sizable increase in the transfer kinetics and critical distance, as direct consequences of strong spin-orbit couplings. Remarkably, the reported R0 value for OsDCBPY (R0 = 88 ± 10 Å) represents one of the largest Förster distances observed in an MOF. Collectively, this work contributes to the general knowledge of energy transfer in materials and provides groundwork for efficient utilization in artificial photosynthetic assemblies.
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Affiliation(s)
- Arnab Chakraborty
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
| | - Stefan Ilic
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
| | - Meng Cai
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
| | - Bradley J Gibbons
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
| | - Xiaozhou Yang
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
| | - Connor C Slamowitz
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
| | - Amanda J Morris
- Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States
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7
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Bhandari S, Roy S, Pramanik S, Chattopadhyay A. Chemical Reactions Involving the Surface of Metal Chalcogenide Quantum Dots. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:14399-14413. [PMID: 31288518 DOI: 10.1021/acs.langmuir.9b01285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
This invited feature article focuses on the chemical reactions involving the surface ions of colloidal quantum dots (Qdots). Emphasis is placed on ion-exchange, redox, and complexation reactions. The pursuit of reactions involving primarily the cations on the surface results in changes in the optical properties of the Qdots and also may confer new properties owing to the newly formed surface species. For example, the cation-exchange reaction, leading to systematic removal of the cations present on the as-synthesized Qdots, enhances the photoluminescence quantum yield. On the other hand, redox reactions, involving the dopant cations in the Qdots, could not only modulate the photoluminescence quantum yield but also give rise to new emission not present in the as-synthesized Qdots. Importantly, the cations present on the surface could be made to react with external organic ligands to form inorganic complexes, thus providing a new species defined as the quantum dot complex (QDC). In the QDC, the properties of Qdots and the inorganic complex are not only present but also enhanced. Furthermore, by varying reaction conditions such as the concentrations of the species and using a mixture of ligands, the properties could be further tuned and multifunctionalization of the Qdot could be achieved. Thus, chemical, magnetic, and optical properties could be simultaneously conferred on the same Qdot. This has helped in externally controlled bioimaging, white light generation involving individual quantum dots, and highly sensitive molecular sensing. Understanding the species (i.e., the newly formed inorganic complex) on the surface of the Qdot and its chemical reactivity provide unique options for futuristic technological applications involving a combination of an inorganic complex and a Qdot.
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Affiliation(s)
- Satyapriya Bhandari
- Department of Chemistry and Centre for Nanotechnology , Indian Institute of Technology Guwahati , Guwahati, Assam 781039 , India
| | - Shilaj Roy
- Department of Chemistry and Centre for Nanotechnology , Indian Institute of Technology Guwahati , Guwahati, Assam 781039 , India
| | - Sabyasachi Pramanik
- Department of Chemistry and Centre for Nanotechnology , Indian Institute of Technology Guwahati , Guwahati, Assam 781039 , India
| | - Arun Chattopadhyay
- Department of Chemistry and Centre for Nanotechnology , Indian Institute of Technology Guwahati , Guwahati, Assam 781039 , India
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Kuznetsov AE. Complexes between core-modified porphyrins ZnP(X)4 (X = P and S) and small semiconductor nanoparticle Zn6S6: are they possible? PHYSICAL SCIENCES REVIEWS 2019. [DOI: 10.1515/psr-2017-0187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The synthetic approach of the anchoring of porphyrins to the surface of semiconductor nanoparticles (NPs) has been realized to form very promising organic/inorganic nanocomposites. They have been of considerable scientific and a wide practical interest including such areas as material science, biomedical applications, and dye-sensitized solar cells (DSSCs). Macrocyclic pyrrole-containing compounds, such as phthalocyanines and porphyrins, can bind to the NP surface by a variety of modes: as monodentate ligands oriented perpendicular to the NP surface, parallel to the NP surface, or, alternatively, in a perpendicular orientation bridging two adjacent NPs. Also, non-covalent (coordination) interactions may be realized between the NP via its metal centers and appropriate meso-attached groups of porphyrins. Recently, we showed computationally that the prominent structural feature of the core-modified MP(X)4 porphyrins (X = P) is their significant distortion from planarity. Motivated by the phenomenon of numerous complexes formation between tetrapyrrols and NPs, we performed the density functional theory (DFT) studies of the complex formation between the core-modified ZnP(X)4 species (X = P and S) without any substituents or linkers and semiconductor NPs, exemplified by small NP Zn6S6. The complexes formation was investigated using the following theoretical approaches: (i) B3LYP/6-31G* and (ii) CAM-B3LYP/6-31G*, both in the gas phase and with implicit effects from C6H6 considered. The calculated binding energies of the complexes studied were found to be significant, varying from ca. 29 up to ca. 69 kcal/mol, depending on the complex and the approach employed.
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Das A, Roy D, Mandal M, Jaiswal C, Ta M, Mandal PK. Carbon Dot with pH Independent Near-Unity Photoluminescence Quantum Yield in an Aqueous Medium: Electrostatics-Induced Förster Resonance Energy Transfer at Submicromolar Concentration. J Phys Chem Lett 2018; 9:5092-5099. [PMID: 30122049 DOI: 10.1021/acs.jpclett.8b02193] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
We report the synthesis and dynamical behavior of a carbon dot (CD) with near 100% photoluminescence quantum yield in water for a very large pH range (1-12). This CD exhibits a rotational correlational time of only ∼130 ps, signifying the whole CD is not exhibiting photoluminescence. Unlike most carbon-based nanoparticles (which act as a quencher of fluorescence), this CD could act as a donor, and the Förster model could account for the experimental observables for the resonance energy transfer (RET) experiment quite well. Based on two dynamical measurements, it could be shown that the fluorescing moiety is located inside the core of the CD. Importantly, for this CD, RET experiments could be performed with a very low concentration (500 nM) of the acceptor. This kind of electrostatics-driven RET at very low concentration is quite important in bioimaging. This ultrabright CD is nontoxic and useful for bioimaging in mesenchymal stem cells.
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Jung S, Chen X. Quantum Dot-Dye Conjugates for Biosensing, Imaging, and Therapy. Adv Healthc Mater 2018; 7:e1800252. [PMID: 29862653 PMCID: PMC6149543 DOI: 10.1002/adhm.201800252] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Revised: 04/17/2018] [Indexed: 01/14/2023]
Abstract
Adding value to the intrinsic properties of quantum dots (QDs), a strategy to conjugate dyes on the surface of QDs offers new opportunities, since the coupling between QD and dyes can be designed to allow Förster resonance energy transfer (FRET) and/or electron transfer (eT). These processes are accompanied by the change of QD and/or dye fluorescence and subsequent photochemical reactions (e.g., generation of 1 O2 ). Based on the change of fluorescence signals by the interaction with biomolecules, QD-dye conjugates are exploited as biosensors for the detection of pH, O2 , nicotinamide adenine dinucleotide (phosphate), ions, proteases, glutathione, and microRNA. QD-dye conjugates also can be modulated by the irradiation of external light; this concept is demonstrated for fluorescence super-resolution imaging as photoactivatable or photoswitchable probes. When QDs are conjugated with photosensitizing dyes, the QD-dye conjugates can generate 1 O2 in a repetitive manner for better cancer treatment, and can also be available for approaches using two-photon excitation or bioluminescence resonance energy transfer mechanisms for deep tissue imaging. Here, the recent advances in QD-dye conjugates, where FRET or eT produces fluorescence readouts or photochemical reactions, are reviewed. Various QD-dye conjugate systems and their biosensing/imaging and photodynamic therapeutics are summarized.
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Affiliation(s)
- Sungwook Jung
- Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Xiaoyuan Chen
- Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, 20892, USA
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Moroz P, Jin Z, Sugiyama Y, Lara D, Razgoniaeva N, Yang M, Kholmicheva N, Khon D, Mattoussi H, Zamkov M. Competition of Charge and Energy Transfer Processes in Donor-Acceptor Fluorescence Pairs: Calibrating the Spectroscopic Ruler. ACS NANO 2018; 12:5657-5665. [PMID: 29883087 DOI: 10.1021/acsnano.8b01451] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Sensing strategies utilizing Förster resonance energy transfer (FRET) are widely used for probing biological phenomena. FRET sensitivity to the donor-acceptor distance makes it ideal for measuring the concentration of a known analyte or determining the spatial separation between fluorescent labels in a macromolecular assembly. The difficulty lies in extracting the FRET efficiency from the acceptor-induced quenching of the donor emission, which may contain a significant non-FRET contribution. Here, we demonstrate a general spectroscopic approach for differentiating between charge transfer and energy transfer (ET) processes in donor-acceptor assemblies and apply the developed method for unravelling the FRET/non-FRET contributions in cyanine dye-semiconductor quantum dot (QD) constructs. The present method relies on correlating the amplitude of the acceptor emission to specific changes in the donor excitation profile in order to extract ET-only transfer efficiencies. Quenching of the donor emission is then utilized to determine the non-ET component, tentatively attributed to the charge transfer. We observe that the latter accounts for 50-99% of donor emission quenching in QD-Cy5 and QD-Cy7 systems, stressing the importance of determining the non-FRET efficiency in a spectroscopic ruler and other FRET-based sensing applications.
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Affiliation(s)
| | - Zhicheng Jin
- Department of Chemistry and Biochemistry , Florida State University , Tallahassee , Florida 32303 , United States
| | - Yuya Sugiyama
- Department of Chemistry and Biochemistry , Florida State University , Tallahassee , Florida 32303 , United States
| | - D'Andree Lara
- Department of Chemistry and Biochemistry , St. Mary's University , San Antonio , Texas 78228 , United States
| | | | | | | | - Dmitriy Khon
- Department of Chemistry and Biochemistry , St. Mary's University , San Antonio , Texas 78228 , United States
| | - Hedi Mattoussi
- Department of Chemistry and Biochemistry , Florida State University , Tallahassee , Florida 32303 , United States
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12
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Das A, Roy D, De CK, Mandal PK. "Where does the fluorescing moiety reside in a carbon dot?" - Investigations based on fluorescence anisotropy decay and resonance energy transfer dynamics. Phys Chem Chem Phys 2018; 20:2251-2259. [PMID: 29303187 DOI: 10.1039/c7cp07411e] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
It has been shown recently that aggregated dyes are responsible for very high fluorescence in a carbon dot (CD). However, what is the location of the fluorescing moiety in CD? Is it inside the CD or attached to the CD's surface? In order to answer these intriguing questions regarding the location of the fluorescing moiety in a CD, we performed rotational anisotropy decay dynamics and resonance energy transfer (RET) dynamics. Rotational correlation time of ∼120 picoseconds nullifies the fact that the whole CD is fluorescing. Instead, we can say that the fluorescing moiety is either embedded inside the CD or attached to the surface of the CD or linked to the CD through covalent bonds. From the fluorescence anisotropy decay dynamics in solvents of different viscosities, we could show that the fluorescing moiety is not attached to the surface of the CD or for that matter, the fluorescing moiety is not in a rigid environment inside the CD. RET dynamical analysis has shown that the time for RET (from CD to acceptor Rh123) is about 5.4 ns and the RET dynamics are independent of the acceptor concentration. Using RET dynamics, we could prove that the fluorescing moiety is not outside the CD; rather, it is inside the CD, but not in a rigid environment. The geometric distance between the fluorescing moiety of the CD and the acceptor (Rh123) has been obtained to be 4.55 nm. Using Förster formulation, the distance between the fluorescing moiety inside the CD and the acceptor Rh123 has been calculated to be 4.24 nm. Thus, we could not only reveal the exact location of the fluorescing moiety in a CD, but we could also demonstrate that unlike for many other nanomaterials, Förster formulation could explain the experimental observables regarding RET involving CD reasonably well.
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Affiliation(s)
- Ananya Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, West-Bengal 741246, India.
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Wang Y, Fry HC, Skinner GE, Schill KM, Duncan TV. Detection and Quantification of Biologically Active Botulinum Neurotoxin Serotypes A and B Using a Förster Resonance Energy Transfer-Based Quantum Dot Nanobiosensor. ACS APPLIED MATERIALS & INTERFACES 2017; 9:31446-31457. [PMID: 28840718 DOI: 10.1021/acsami.7b08736] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Botulinum neurotoxin (BoNT) is the most potent toxin known. The ingestion of food contaminated with biologically active BoNT causes foodborne botulism, which can lead to respiratory paralysis, coma, and death after ingestion of as little as 70 μg for a 70 kg human. Because of its lethality and challenges associated with current detection methods, there is an urgent need for highly sensitive rapid screening techniques capable of detecting biologically active BoNT. Here, we describe a Förster resonance energy transfer-based nanobiosensor that uses quantum dots (QDs) and two specific quencher-labeled peptide probes to detect and differentiate two biologically active forms of BoNT, serotypes A and B, which were responsible for 80% of human foodborne botulism cases in the U.S. from 2012 to 2015. Each peptide probe contains an enzymatic cleavage site specific to only one serotype. QDs were selected based on the spectral overlap with the quenchers. In the presence of the target BoNT serotype, the peptide probe is cleaved and the quenching of QD photoluminescence (PL) is reduced, giving a signal that is easily detected by a PL spectrophotometer. This sensor performance was evaluated with light chains of BoNT/A and BoNT/B (LcA and LcB), catalytic domains of the respective serotypes. LcA and LcB were detected in 3 h with limits of detection of 0.2 and 2 ng/mL, respectively. The specificity of the sensor was evaluated, and no cross-reactivity from nontarget serotypes was observed with 2 h of incubation. Because each serotype-specific peptide is conjugated to a QD with a unique emission wavelength, multiple biologically active BoNT serotypes could be detected in one PL spectrum. The sensor was also shown to be responsive to BoNT/A and BoNT/B holotoxins. Good performance of this sensor implies its potential application as a rapid screening method for biologically active BoNT/A and BoNT/B in the laboratory and in the field.
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Affiliation(s)
- Yun Wang
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , 6502 S. Archer Road, Bedford Park, Cook County, Illinois 60501, United States
| | - H Christopher Fry
- Center for Nanoscale Materials, Argonne National Laboratory , 9700 S. Cass Avenue, Lemont, DuPage County, Illinois 60439, United States
| | - Guy E Skinner
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , 6502 S. Archer Road, Bedford Park, Cook County, Illinois 60501, United States
| | - Kristin M Schill
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , 6502 S. Archer Road, Bedford Park, Cook County, Illinois 60501, United States
| | - Timothy V Duncan
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , 6502 S. Archer Road, Bedford Park, Cook County, Illinois 60501, United States
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14
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Nag OK, Stewart MH, Deschamps JR, Susumu K, Oh E, Tsytsarev V, Tang Q, Efros AL, Vaxenburg R, Black BJ, Chen Y, O’Shaughnessy TJ, North SH, Field LD, Dawson PE, Pancrazio JJ, Medintz IL, Chen Y, Erzurumlu RS, Huston AL, Delehanty JB. Quantum Dot-Peptide-Fullerene Bioconjugates for Visualization of in Vitro and in Vivo Cellular Membrane Potential. ACS NANO 2017; 11:5598-5613. [PMID: 28514167 PMCID: PMC6001310 DOI: 10.1021/acsnano.7b00954] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We report the development of a quantum dot (QD)-peptide-fullerene (C60) electron transfer (ET)-based nanobioconjugate for the visualization of membrane potential in living cells. The bioconjugate is composed of (1) a central QD electron donor, (2) a membrane-inserting peptidyl linker, and (3) a C60 electron acceptor. The photoexcited QD donor engages in ET with the C60 acceptor, resulting in quenching of QD photoluminescence (PL) that tracks positively with the number of C60 moieties arrayed around the QD. The nature of the QD-capping ligand also modulates the quenching efficiency; a neutral ligand coating facilitates greater QD quenching than a negatively charged carboxylated ligand. Steady-state photophysical characterization confirms an ET-driven process between the donor-acceptor pair. When introduced to cells, the amphiphilic QD-peptide-C60 bioconjugate labels the plasma membrane by insertion of the peptide-C60 portion into the hydrophobic bilayer, while the hydrophilic QD sits on the exofacial side of the membrane. Depolarization of cellular membrane potential augments the ET process, which is manifested as further quenching of QD PL. We demonstrate in HeLa cells, PC12 cells, and primary cortical neurons significant QD PL quenching (ΔF/F0 of 2-20% depending on the QD-C60 separation distance) in response to membrane depolarization with KCl. Further, we show the ability to use the QD-peptide-C60 probe in combination with conventional voltage-sensitive dyes (VSDs) for simultaneous two-channel imaging of membrane potential. In in vivo imaging of cortical electrical stimulation, the optical response of the optimal QD-peptide-C60 configuration exhibits temporal responsivity to electrical stimulation similar to that of VSDs. Notably, however, the QD-peptide-C60 construct displays 20- to 40-fold greater ΔF/F0 than VSDs. The tractable nature of the QD-peptide-C60 system offers the advantages of ease of assembly, large ΔF/F0, enhanced photostability, and high throughput without the need for complicated organic synthesis or genetic engineering, respectively, that is required of traditional VSDs and fluorescent protein constructs.
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Affiliation(s)
- Okhil K. Nag
- Center for Bio/Molecular Science and Engineering, Code 6900
| | | | | | - Kimihiro Susumu
- Optical Sciences Division, Code 5600
- Sotera Defense Solutions, Columbia, Maryland 21046, United States
| | - Eunkeu Oh
- Optical Sciences Division, Code 5600
- Sotera Defense Solutions, Columbia, Maryland 21046, United States
| | - Vassiliy Tsytsarev
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - Qinggong Tang
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Alexander L. Efros
- Materials and Science and Technology Division, Code 6300, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Roman Vaxenburg
- Computational Materials Science Center, George Mason University, Fairfax, Virginia 22030, United States
| | - Bryan J. Black
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas 75080, United States
| | - YungChia Chen
- Center for Bio/Molecular Science and Engineering, Code 6900
| | - Thomas J. O’Shaughnessy
- Materials and Science and Technology Division, Code 6300, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | | | - Lauren D. Field
- Center for Bio/Molecular Science and Engineering, Code 6900
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Philip E. Dawson
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Joseph J. Pancrazio
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas 75080, United States
| | | | - Yu Chen
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, United States
| | - Reha S. Erzurumlu
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201, United States
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15
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Bodunov EN, Antonov YA, Simões Gamboa AL. On the origin of stretched exponential (Kohlrausch) relaxation kinetics in the room temperature luminescence decay of colloidal quantum dots. J Chem Phys 2017; 146:114102. [DOI: 10.1063/1.4978396] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- E. N. Bodunov
- Department of Physics, Emperor Alexander I St. Petersburg State Transport University, 190031 St. Petersburg, Russia
| | - Yu. A. Antonov
- Department of Physics, Emperor Alexander I St. Petersburg State Transport University, 190031 St. Petersburg, Russia
| | - A. L. Simões Gamboa
- International Research and Education Centre for Physics of Nanostructures, ITMO University, 197101 St. Petersburg, Russia
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16
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Riedel M, Sabir N, Scheller FW, Parak WJ, Lisdat F. Connecting quantum dots with enzymes: mediator-based approaches for the light-directed read-out of glucose and fructose oxidation. NANOSCALE 2017; 9:2814-2823. [PMID: 28155960 DOI: 10.1039/c7nr00091j] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The combination of the biocatalytic features of enzymes with the unique physical properties of nanoparticles in a biohybrid system provides a promising approach for the development of advanced bioelectrocatalytic devices. This study describes the construction of photoelectrochemical signal chains based on CdSe/ZnS quantum dot (QD) modified gold electrodes as light switchable elements, and low molecular weight redox molecules for the combination with different biocatalysts. Photoelectrochemical and photoluminescence experiments verify that electron transfer can be achieved between the redox molecules hexacyanoferrate and ferrocene, and the QDs under illumination. Since for both redox mediators a concentration dependent photocurrent change has been found, light switchable enzymatic signal chains are built up with fructose dehydrogenase (FDH) and pyrroloquinoline quinone-dependent glucose dehydrogenase ((PQQ)GDH) for the detection of sugars. After immobilization of the enzymes at the QD electrode the biocatalytic oxidation of the substrates can be followed by conversion of the redox mediator in solution and subsequent detection at the QD electrode. Furthermore, (PQQ)GDH has been assembled together with ferrocenecarboxylic acid on top of the QD electrode for the construction of a funtional biohybrid architecture, showing that electron transfer can be realized from the enzyme over the redox mediator to the QDs and subsequently to the electrode in a completely immobilized fashion. The results obtained here do not only provide the basis for light-switchable biosensing and bioelectrocatalytic applications, but may also open the way for self-driven point-of-care systems by combination with solar cell approaches (power generation at the QD electrode by enzymatic substrate consumption).
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Affiliation(s)
- M Riedel
- Biosystems Technology, Institute for Applied Life Sciences, Technical University Wildau, Hochschulring 1, D-15745 Wildau, Germany.
| | - N Sabir
- Fachbereich Physik, Philips University Marburg, Renthof 5, D-35032 Marburg, Germany
| | - F W Scheller
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Strasse 25-26, D-14476 Potsdam, Germany
| | - W J Parak
- Fachbereich Physik, Philips University Marburg, Renthof 5, D-35032 Marburg, Germany
| | - F Lisdat
- Biosystems Technology, Institute for Applied Life Sciences, Technical University Wildau, Hochschulring 1, D-15745 Wildau, Germany.
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17
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Hildebrandt N, Spillmann CM, Algar WR, Pons T, Stewart MH, Oh E, Susumu K, Díaz SA, Delehanty JB, Medintz IL. Energy Transfer with Semiconductor Quantum Dot Bioconjugates: A Versatile Platform for Biosensing, Energy Harvesting, and Other Developing Applications. Chem Rev 2016; 117:536-711. [DOI: 10.1021/acs.chemrev.6b00030] [Citation(s) in RCA: 457] [Impact Index Per Article: 57.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Niko Hildebrandt
- NanoBioPhotonics
Institut d’Electronique Fondamentale (I2BC), Université Paris-Saclay, Université Paris-Sud, CNRS, 91400 Orsay, France
| | | | - W. Russ Algar
- Department
of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Thomas Pons
- LPEM;
ESPCI Paris, PSL Research University; CNRS; Sorbonne Universités, UPMC, F-75005 Paris, France
| | | | - Eunkeu Oh
- Sotera Defense Solutions, Inc., Columbia, Maryland 21046, United States
| | - Kimihiro Susumu
- Sotera Defense Solutions, Inc., Columbia, Maryland 21046, United States
| | - Sebastian A. Díaz
- American Society for Engineering Education, Washington, DC 20036, United States
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18
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Ji X, Wang W, Mattoussi H. Effects of separation distance on the charge transfer interactions in quantum dot-dopamine assemblies. Phys Chem Chem Phys 2016; 17:10108-17. [PMID: 25789996 DOI: 10.1039/c5cp00462d] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We explored the effects of changing the separation distance on the charge transfer interactions between luminescent QD and proximal dopamine (in QD-dopamine assemblies), and the ensuing photoluminescence (PL) quenching. The separation distance was controlled using a tunable size bridge between the QD and dopamine via a poly(ethylene glycol) (PEG) chain where the average number of monomers was discretely varied. Using steady-state and time-resolved fluorescence measurements, we found that the photoluminescence losses were substantially more pronounced for QD-dopamine complexes prepared with the shortest PEG bridge, but progressively decreased with increasing PEG size. We also found that the charge transfer interactions can be affected by the nature of the capping ligand used. In particular, we found that interactions and PL quenching in these assemblies tracked the effects of separation distance, conjugate valence and the energy mismatch between the dopamine redox levels and QD energy levels, when a compact zwitterion was used to control the conjugate configuration. However, additional effects of shielding the access of reactive dopamine to amine groups on the QD surface, when a longer inert PEG ligand was used, were found to produce heterogeneous conjugates, alter the interactions and produce weaker PL quenching.
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Affiliation(s)
- Xin Ji
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, Florida 32306, USA.
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19
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Ray PC, Fan Z, Crouch RA, Sinha SS, Pramanik A. Nanoscopic optical rulers beyond the FRET distance limit: fundamentals and applications. Chem Soc Rev 2015; 43:6370-404. [PMID: 24902784 DOI: 10.1039/c3cs60476d] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In the last few decades, Förster resonance energy transfer (FRET) based spectroscopy rulers have served as a key tool for the understanding of chemical and biochemical processes, even at the single molecule level. Since the FRET process originates from dipole-dipole interactions, the length scale of a FRET ruler is limited to a maximum of 10 nm. Recently, scientists have reported a nanomaterial based long-range optical ruler, where one can overcome the FRET optical ruler distance dependence limit, and which can be very useful for monitoring biological processes that occur across a greater distance than the 10 nm scale. Advancement of nanoscopic long range optical rulers in the last ten years indicate that, in addition to their long-range capability, their brightness, long lifetime, lack of blinking, and chemical stability make nanoparticle based rulers a good choice for long range optical probes. The current review discusses the basic concepts and unique light-focusing properties of plasmonic nanoparticles which are useful in the development of long range one dimensional to three dimensional optical rulers. In addition, to provide the readers with an overview of the exciting opportunities within this field, this review discusses the applications of long range rulers for monitoring biological and chemical processes. At the end, we conclude by speculating on the role of long range optical rulers in future scientific research and discuss possible problems, outlooks and future needs in the use of optical rulers for technological applications.
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Affiliation(s)
- Paresh Chandra Ray
- Department of Chemistry and Biochemistry, Jackson State University, Jackson, MS, USA.
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20
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Zhu X, Hu J, Zhao Z, Sun M, Chi X, Wang X, Gao J. Kinetic and sensitive analysis of tyrosinase activity using electron transfer complexes: in vitro and intracellular study. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:862-870. [PMID: 25285706 DOI: 10.1002/smll.201401595] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 07/31/2014] [Indexed: 06/03/2023]
Abstract
Tyrosinase is an important marker of human diseases such as the neurodegeneration associated with Parkinson's disease and melanoma. Sensitive detection of tyrosinase activity in vitro and inside cells is of great significance to medical diagnostics and skin disorder treatments. With unique photophysical properties, semiconductor quantum dots (QDs) are employed as photoluminescent platforms for various biosensing, in particular for the detection of enzyme activities. In this work, QDs are functionalized with tyrosine and zwitterionic molecules to construct a nanometer-scale scaffold (QD-Tyr conjugate), and this is used to test tyrosinase activity in vitro and inside cells. Tyrosinase oxidizes tyrosine to dopachrome and switches on the electron-transfer access, which relates to fluorescence quenching. High quenching efficiency is achieved by shortening the distance between the electron donors and acceptors, which is attributed to the small size of the conjugated tyrosine. Enzymatic process curves reveal the enhanced enzymatic activity on the conjugated nanoparticle substrate, which leads to highly sensitive detection of tyrosinase (as low as 1 nM). It is also demonstrated that QD-Tyr conjugates can sensitively probe intracellular tyrosinase in melanoma cells, which promises great potential in disease monitoring and medical diagnostics.
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Affiliation(s)
- Xianglong Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, The Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
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21
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Elward JM, Chakraborty A. Effect of Heterojunction on Exciton Binding Energy and Electron–Hole Recombination Probability in CdSe/ZnS Quantum Dots. J Chem Theory Comput 2015; 11:462-71. [DOI: 10.1021/ct500548x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jennifer M. Elward
- Army Research
Laboratory, Aberdeen Proving Ground, Aberdeen, Maryland 21005, United States
| | - Arindam Chakraborty
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
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22
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Bhandari S, Roy S, Pramanik S, Chattopadhyay A. Double channel emission from a redox active single component quantum dot complex. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:551-561. [PMID: 25459633 DOI: 10.1021/la504139m] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Herein we report the generation and control of double channel emission from a single component system following a facile complexation reaction between a Mn(2+) doped ZnS colloidal quantum dot (Qdot) and an organic ligand (8-hydroxy quinoline; HQ). The double channel emission of the complexed quantum dot-called the quantum dot complex (QDC)-originates from two independent pathways: one from the complex (ZnQ2) formed on the surface of the Qdot and the other from the dopant Mn(2+) ions of the Qdot. Importantly, reaction of ZnQ2·2H2O with the Qdot resulted in the same QDC formation. The emission at 500 nm with an excitation maximum at 364 nm is assigned to the surface complex involving ZnQ2 and a dangling sulfide bond. On the other hand, the emission at 588 nm-with an excitation maximum at 330 nm-which is redox tunable, is ascribed to Mn(2+) dopant. The ZnQ2 complex while present in QDC has superior thermal stability in comparison to the bare complex. Interestingly, while the emission of Mn(2+) was quenched by an electron quencher (benzoquinone), that due to the surface complex remained unaffected. Further, excitation wavelength dependent tunability in chromaticity color coordinates makes the QDC a potential candidate for fabricating a light emitting device of desired color output.
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Affiliation(s)
- Satyapriya Bhandari
- Department of Chemistry and ‡Centre for Nanotechnology, Indian Institute of Technology Guwahati , Guwahati-781039, Assam, India
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23
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Kumar P, Pascher T, Tachiya M, Pal SK. Global analysis of quenching of the time-resolved emission of ZnO nanocrystals by adsorbed rhodamine B on the basis of Tachiya theory. J Photochem Photobiol A Chem 2015. [DOI: 10.1016/j.jphotochem.2014.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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24
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Zou HY, Gao PF, Gao MX, Huang CZ. Polydopamine-embedded Cu2−xSe nanoparticles as a sensitive biosensing platform through the coupling of nanometal surface energy transfer and photo-induced electron transfer. Analyst 2015; 140:4121-9. [DOI: 10.1039/c5an00221d] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
This study innovatively highlights the mechanistic details of NSET and PET (NSET©PET) coupling processes, and the disclosed mechanism provides new opportunities for sensitive biosensing applications.
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Affiliation(s)
- Hong Yan Zou
- Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Southwest University)
- Ministry of Education
- College of Pharmaceutical Sciences
- Southwest University
- Chongqing
| | - Peng Fei Gao
- Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Southwest University)
- Ministry of Education
- College of Pharmaceutical Sciences
- Southwest University
- Chongqing
| | - Ming Xuan Gao
- College of Chemistry and Chemical Engineering
- Southwest University
- Chongqing
- P. R. China
| | - Cheng Zhi Huang
- Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Southwest University)
- Ministry of Education
- College of Pharmaceutical Sciences
- Southwest University
- Chongqing
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25
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Si HY, Wang LJ, Feng WJ, Zhang HL, Zhu H, Zhao JJ, Ding ZL, Li YT. Facilely controlling the Förster energy transfer efficiency of dendron encapsulated conjugated organic molecular wire–CdSe quantum dot nanostructures. NEW J CHEM 2015. [DOI: 10.1039/c4nj01888e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
On Den-OPE–CdSe nanostructures, as the size of the dendrimer increases, the energy transfer efficiency from Den-OPEs to CdSe QDs enhances.
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Affiliation(s)
- Hua-Yan Si
- School of Materials Science and Engineering
- Shijiazhuang Tiedao University
- Shijiazhuang 050043
- China
- Hebei Provincial Key Laboratory of Traffic Engineering materials
| | - Le-Jia Wang
- State Key Laboratory of Applied Organic Chemistry
- College of Chemistry and Chemical Engineering
- Lanzhou University
- 730000 Lanzhou
- China
| | - Wen-Jie Feng
- Mechanics Engineering Department
- Shijiazhuang Tiedao University
- Shijiazhuang 050043
- China
| | - Hao-Li Zhang
- State Key Laboratory of Applied Organic Chemistry
- College of Chemistry and Chemical Engineering
- Lanzhou University
- 730000 Lanzhou
- China
| | - Hao Zhu
- School of Materials Science and Engineering
- Shijiazhuang Tiedao University
- Shijiazhuang 050043
- China
| | - Jin-Jin Zhao
- School of Materials Science and Engineering
- Shijiazhuang Tiedao University
- Shijiazhuang 050043
- China
| | - Zhan-Lai Ding
- School of Materials Science and Engineering
- Shijiazhuang Tiedao University
- Shijiazhuang 050043
- China
| | - Yan-Ting Li
- School of Materials Science and Engineering
- Shijiazhuang Tiedao University
- Shijiazhuang 050043
- China
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26
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Algar WR, Stewart MH, Scott AM, Moon WJ, Medintz IL. Quantum dots as platforms for charge transfer-based biosensing: challenges and opportunities. J Mater Chem B 2014; 2:7816-7827. [DOI: 10.1039/c4tb00985a] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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27
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Buckhout-White S, Claussen JC, Melinger JS, Dunningham Z, Ancona MG, Goldman ER, Medintz IL. A triangular three-dye DNA switch capable of reconfigurable molecular logic. RSC Adv 2014. [DOI: 10.1039/c4ra10580j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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28
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Breger J, Delehanty JB, Medintz IL. Continuing progress toward controlled intracellular delivery of semiconductor quantum dots. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2014; 7:131-51. [PMID: 25154379 PMCID: PMC4345423 DOI: 10.1002/wnan.1281] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 04/21/2014] [Accepted: 05/28/2014] [Indexed: 01/22/2023]
Abstract
The biological applications of luminescent semiconductor quantum dots (QDs) continue to grow at a nearly unabated pace. This growth is driven, in part, by their unique photophysical and physicochemical properties which have allowed them to be used in many different roles in cellular biology including: as superior fluorophores for a wide variety of cellular labeling applications; as active platforms for assembly of nanoscale sensors; and, more recently, as a powerful tool to understand the mechanisms of nanoparticle mediated drug delivery. Given that controlled cellular delivery is at the intersection of all these applications, the latest progress in delivering QDs to cells is examined here. A brief discussion of relevant considerations including the importance of materials preparation and bioconjugation along with the continuing issue of endosomal sequestration is initially provided for context. Methods for the cellular delivery of QDs are then highlighted including those based on passive exposure, facilitated strategies that utilize peptides or polymers and fully active modalities such as electroporation and other mechanically based methods. Following on this, the exciting advent of QD cellular delivery using multiple or combined mechanisms is then previewed. Several recent methods reporting endosomal escape of QD materials in cells are also examined in detail with a focus on the mechanisms by which access to the cytosol is achieved. The ongoing debate over QD cytotoxicity is also discussed along with a perspective on how this field will continue to evolve in the future.
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Affiliation(s)
- Joyce Breger
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, DC, USA
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29
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Scott AM, Algar WR, Stewart MH, Trammell SA, Blanco-Canosa JB, Dawson PE, Deschamps JR, Goswami R, Oh E, Huston AL, Medintz IL. Probing the Quenching of Quantum Dot Photoluminescence by Peptide-Labeled Ruthenium(II) Complexes. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2014; 118:9239-9250. [PMID: 24817922 PMCID: PMC4010286 DOI: 10.1021/jp501039w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 03/31/2014] [Indexed: 05/21/2023]
Abstract
Charge transfer processes with semiconductor quantum dots (QDs) have generated much interest for potential utility in energy conversion. Such configurations are generally nonbiological; however, recent studies have shown that a redox-active ruthenium(II)-phenanthroline complex (Ru2+-phen) is particularly efficient at quenching the photoluminescence (PL) of QDs, and this mechanism demonstrates good potential for application as a generalized biosensing detection modality since it is aqueous compatible. Multiple possibilities for charge transfer and/or energy transfer mechanisms exist within this type of assembly, and there is currently a limited understanding of the underlying photophysical processes in such biocomposite systems where nanomaterials are directly interfaced with biomolecules such as proteins. Here, we utilize redox reactions, steady-state absorption, PL spectroscopy, time-resolved PL spectroscopy, and femtosecond transient absorption spectroscopy (FSTA) to investigate PL quenching in biological assemblies of CdSe/ZnS QDs formed with peptide-linked Ru2+-phen. The results reveal that QD quenching requires the Ru2+ oxidation state and is not consistent with Förster resonance energy transfer, strongly supporting a charge transfer mechanism. Further, two colors of CdSe/ZnS core/shell QDs with similar macroscopic optical properties were found to have very different rates of charge transfer quenching, by Ru2+-phen with the key difference between them appearing to be the thickness of their ZnS outer shell. The effect of shell thickness was found to be larger than the effect of increasing distance between the QD and Ru2+-phen when using peptides of increasing persistence length. FSTA and time-resolved upconversion PL results further show that exciton quenching is a rather slow process consistent with other QD conjugate materials that undergo hole transfer. An improved understanding of the QD-Ru2+-phen system can allow for the design of more sophisticated charge-transfer-based biosensors using QD platforms.
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Affiliation(s)
- Amy M. Scott
- Department
of Chemistry, University of Miami, 1301 Memorial Drive, Miami, Florida 33146, United States
- E-mail:
| | - W. Russ Algar
- Center for Bio/Molecular Science and Engineering, Code 6900, Optical Sciences Division,
Code 5611, and Material Sciences and Technology, Code 6351, U.S. Naval Research Laboratory, Washington, DC 20375, United States
| | - Michael H. Stewart
- Center for Bio/Molecular Science and Engineering, Code 6900, Optical Sciences Division,
Code 5611, and Material Sciences and Technology, Code 6351, U.S. Naval Research Laboratory, Washington, DC 20375, United States
| | - Scott A. Trammell
- Center for Bio/Molecular Science and Engineering, Code 6900, Optical Sciences Division,
Code 5611, and Material Sciences and Technology, Code 6351, U.S. Naval Research Laboratory, Washington, DC 20375, United States
| | - Juan B. Blanco-Canosa
- Departments
of Cell Biology and Chemistry, The Scripps
Research Institute, La Jolla, California 92037, United States
| | - Philip E. Dawson
- Departments
of Cell Biology and Chemistry, The Scripps
Research Institute, La Jolla, California 92037, United States
| | - Jeffrey R. Deschamps
- Center for Bio/Molecular Science and Engineering, Code 6900, Optical Sciences Division,
Code 5611, and Material Sciences and Technology, Code 6351, U.S. Naval Research Laboratory, Washington, DC 20375, United States
| | - Ramasis Goswami
- Center for Bio/Molecular Science and Engineering, Code 6900, Optical Sciences Division,
Code 5611, and Material Sciences and Technology, Code 6351, U.S. Naval Research Laboratory, Washington, DC 20375, United States
| | - Eunkeu Oh
- Center for Bio/Molecular Science and Engineering, Code 6900, Optical Sciences Division,
Code 5611, and Material Sciences and Technology, Code 6351, U.S. Naval Research Laboratory, Washington, DC 20375, United States
- Sotera Defense
Solutions, Columbia, Maryland 21046, United
States
| | - Alan L. Huston
- Center for Bio/Molecular Science and Engineering, Code 6900, Optical Sciences Division,
Code 5611, and Material Sciences and Technology, Code 6351, U.S. Naval Research Laboratory, Washington, DC 20375, United States
| | - Igor L. Medintz
- Center for Bio/Molecular Science and Engineering, Code 6900, Optical Sciences Division,
Code 5611, and Material Sciences and Technology, Code 6351, U.S. Naval Research Laboratory, Washington, DC 20375, United States
- E-mail:
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30
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Gilbert B, Katz JE, Huse N, Zhang X, Frandsen C, Falcone RW, Waychunas GA. Ultrafast electron and energy transfer in dye-sensitized iron oxide and oxyhydroxide nanoparticles. Phys Chem Chem Phys 2014; 15:17303-13. [PMID: 24018485 DOI: 10.1039/c3cp53368a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
An emerging area in chemical science is the study of solid-phase redox reactions using ultrafast time-resolved spectroscopy. We have used molecules of the photoactive dye 2',7'-dichlorofluorescein (DCF) anchored to the surface of iron(III) oxide nanoparticles to create iron(II) surface atoms via photo-initiated interfacial electron transfer. This approach enables time-resolved study of the fate and mobility of electrons within the solid phase. However, complete analysis of the ultrafast processes following dye photoexcitation of the sensitized iron(III) oxide nanoparticles has not been reported. We addressed this topic by performing femtosecond transient absorption (TA) measurements of aqueous suspensions of uncoated and DCF-sensitized iron oxide and oxyhydroxide nanoparticles, and an aqueous iron(III)-dye complex. Following light absorption, excited state relaxation times of the dye of 115-310 fs were found for all samples. Comparison between TA dynamics on uncoated and dye-sensitized hematite nanoparticles revealed the dye de-excitation pathway to consist of a competition between electron and energy transfer to the nanoparticles. We analyzed the TA data for hematite nanoparticles using a four-state model of the dye-sensitized system, finding electron and energy transfer to occur on the same ultrafast timescale. The interfacial electron transfer rates for iron oxides are very close to those previously reported for DCF-sensitized titanium dioxide (for which dye-oxide energy transfer is energetically forbidden) even though the acceptor states are different. Comparison of the alignment of the excited states of the dye and the unoccupied states of these oxides showed that the dye injects into acceptor states of different symmetry (Ti t2gvs. Fe eg).
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Affiliation(s)
- Benjamin Gilbert
- Earth Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
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31
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Blanco-Canosa JB, Wu M, Susumu K, Petryayeva E, Jennings TL, Dawson PE, Algar WR, Medintz IL. Recent progress in the bioconjugation of quantum dots. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2013.08.030] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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Algar WR, Kim H, Medintz IL, Hildebrandt N. Emerging non-traditional Förster resonance energy transfer configurations with semiconductor quantum dots: Investigations and applications. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2013.07.015] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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33
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Bhandari S, Roy S, Chattopadhyay A. Enhanced photoluminescence and thermal stability of zinc quinolate following complexation on the surface of quantum dots. RSC Adv 2014. [DOI: 10.1039/c4ra03341h] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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34
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Hernández-Gil J, Ferrer S, Castiñeiras A, Liu-González M, Lloret F, Ribes Á, Čoga L, Bernecker A, Mareque-Rivas JC. Two Novel Ternary Dicopper(II) μ-Guanazole Complexes with Aromatic Amines Strongly Activated by Quantum Dots for DNA Cleavage. Inorg Chem 2013; 53:578-93. [DOI: 10.1021/ic4027249] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Javier Hernández-Gil
- Departament
de Química Inorgànica, Universitat de València, Vicent Andrés
Estellés s/n, 46100 Burjassot,
Valencia, Spain
| | - Sacramento Ferrer
- Departament
de Química Inorgànica, Universitat de València, Vicent Andrés
Estellés s/n, 46100 Burjassot,
Valencia, Spain
| | - Alfonso Castiñeiras
- Departamento
de Química Inorgánica, Universidad de Santiago de Compostela, Campus Universitario
Sur, E-15782 Santiago de Compostela, Spain
| | - Malva Liu-González
- S.C.S.I.E., Universitat de València, Dr.
Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Francesc Lloret
- Institut
de Ciència Molecular, Universitat de València, Catedràtic
José Beltrán n° 2, 46980 Paterna, Valencia, Spain
| | - Ángela Ribes
- Departament
de Química Inorgànica, Universitat de València, Vicent Andrés
Estellés s/n, 46100 Burjassot,
Valencia, Spain
| | - Lucija Čoga
- Departament
de Química Inorgànica, Universitat de València, Vicent Andrés
Estellés s/n, 46100 Burjassot,
Valencia, Spain
| | - Anja Bernecker
- Cooperative Centre for Research in Biomaterials (CIC biomaGUNE), 20009 San Sebastián, Spain
| | - Juan C. Mareque-Rivas
- Cooperative Centre for Research in Biomaterials (CIC biomaGUNE), 20009 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
- Departmento
de Bioquimica y Biologia Molecular, Universidad del Pais Vasco, 48940 Leioa, Spain
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35
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Stewart MH, Huston AL, Scott AM, Oh E, Algar WR, Deschamps JR, Susumu K, Jain V, Prasuhn DE, Blanco-Canosa J, Dawson PE, Medintz IL. Competition between Förster resonance energy transfer and electron transfer in stoichiometrically assembled semiconductor quantum dot-fullerene conjugates. ACS NANO 2013; 7:9489-505. [PMID: 24128175 DOI: 10.1021/nn403872x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Understanding how semiconductor quantum dots (QDs) engage in photoinduced energy transfer with carbon allotropes is necessary for enhanced performance in solar cells and other optoelectronic devices along with the potential to create new types of (bio)sensors. Here, we systematically investigate energy transfer interactions between C60 fullerenes and four different QDs, composed of CdSe/ZnS (type I) and CdSe/CdS/ZnS (quasi type II), with emission maxima ranging from 530 to 630 nm. C60-pyrrolidine tris-acid was first coupled to the N-terminus of a hexahistidine-terminated peptide via carbodiimide chemistry to yield a C60-labeled peptide (pepC60). This peptide provided the critical means to achieve ratiometric self-assembly of the QD-(pepC60) nanoheterostructures by exploiting metal affinity coordination to the QD surface. Controlled QD-(pepC60)N bioconjugates were prepared by discretely increasing the ratio (N) of pepC60 assembled per QD in mixtures of dimethyl sulfoxide and buffer; this mixed organic/aqueous approach helped alleviate issues of C60 solubility. An extensive set of control experiments were initially performed to verify the specific and ratiometric nature of QD-(pepC60)N assembly. Photoinitiated energy transfer in these hybrid organic-inorganic systems was then interrogated using steady-state and time-resolved fluorescence along with ultrafast transient absorption spectroscopy. Coordination of pepC60 to the QD results in QD PL quenching that directly tracks with the number of peptides displayed around the QD. A detailed photophysical analysis suggests a competition between electron transfer and Förster resonance energy transfer from the QD to the C60 that is dependent upon a complex interplay of pepC60 ratio per QD, the presence of underlying spectral overlap, and contributions from QD size. These results highlight several important factors that must be considered when designing QD-donor/C60-acceptor systems for potential optoelectronic and biosensing applications.
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Affiliation(s)
- Michael H Stewart
- Optical Sciences Division, Code 5611, ‡Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory , Washington, DC 20375, United States
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36
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Spillmann CM, Ancona MG, Buckhout-White S, Algar WR, Stewart MH, Susumu K, Huston AL, Goldman ER, Medintz IL. Achieving effective terminal exciton delivery in quantum dot antenna-sensitized multistep DNA photonic wires. ACS NANO 2013; 7:7101-7118. [PMID: 23844838 DOI: 10.1021/nn402468t] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Assembling DNA-based photonic wires around semiconductor quantum dots (QDs) creates optically active hybrid architectures that exploit the unique properties of both components. DNA hybridization allows positioning of multiple, carefully arranged fluorophores that can engage in sequential energy transfer steps while the QDs provide a superior energy harvesting antenna capacity that drives a Förster resonance energy transfer (FRET) cascade through the structures. Although the first generation of these composites demonstrated four-sequential energy transfer steps across a distance >150 Å, the exciton transfer efficiency reaching the final, terminal dye was estimated to be only ~0.7% with no concomitant sensitized emission observed. Had the terminal Cy7 dye utilized in that construct provided a sensitized emission, we estimate that this would have equated to an overall end-to-end ET efficiency of ≤ 0.1%. In this report, we demonstrate that overall energy flow through a second generation hybrid architecture can be significantly improved by reengineering four key aspects of the composite structure: (1) making the initial DNA modification chemistry smaller and more facile to implement, (2) optimizing donor-acceptor dye pairings, (3) varying donor-acceptor dye spacing as a function of the Förster distance R0, and (4) increasing the number of DNA wires displayed around each central QD donor. These cumulative changes lead to a 2 orders of magnitude improvement in the exciton transfer efficiency to the final terminal dye in comparison to the first-generation construct. The overall end-to-end efficiency through the optimized, five-fluorophore/four-step cascaded energy transfer system now approaches 10%. The results are analyzed using Förster theory with various sources of randomness accounted for by averaging over ensembles of modeled constructs. Fits to the spectra suggest near-ideal behavior when the photonic wires have two sequential acceptor dyes (Cy3 and Cy3.5) and exciton transfer efficiencies approaching 100% are seen when the dye spacings are 0.5 × R0. However, as additional dyes are included in each wire, strong nonidealities appear that are suspected to arise predominantly from the poor photophysical performance of the last two acceptor dyes (Cy5 and Cy5.5). The results are discussed in the context of improving exciton transfer efficiency along photonic wires and the contributions these architectures can make to understanding multistep FRET processes.
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Affiliation(s)
- Christopher M Spillmann
- Center for Bio/Molecular Science and Engineering, Code 6900, US Naval Research Laboratory, Washington, DC 20375, United States
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