1
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Anjali Devi JS, Madanan Anju S, Lekha GM, Aparna RS, George S. Luminescent carbon dots versus quantum dots and gold nanoclusters as sensors. NANOSCALE HORIZONS 2024. [PMID: 39037443 DOI: 10.1039/d4nh00107a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
Ultra-small nanoparticles, including quantum dots, gold nanoclusters (AuNCs) and carbon dots (CDs), have emerged as a promising class of fluorescent material because of their molecular-like properties and widespread applications in sensing and imaging. However, the fluorescence properties of ultra-small gold nanoparticles (i.e., AuNCs) and CDs are more complicated and well distinguished from conventional quantum dots or organic dye molecules. At this frontier, we highlight recent developments in the fundamental understanding of the fluorescence emission mechanism of these ultra-small nanoparticles. Moreover, this review carefully analyses the underlying principles of ultra-small nanoparticle sensors. We expect that this information on ultra-small nanoparticles will fuel research aimed at achieving precise control over their fluorescence properties and the broadening of their applications.
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Affiliation(s)
- J S Anjali Devi
- Department of Chemistry, School of Physical and Mathematical Sciences, University of Kerala, Thiruvananthapuram 695581, Kerala, India.
- School of Chemical Sciences, Mahatma Gandhi University, Priyadarsini Hills P. O., Kottayam 686560, Kerala, India
- Department of Chemistry, Kannur University, Swami Anandatheertha Campus, Payyanur, Edat P. O. Kannur 670327, Kerala, India
| | - S Madanan Anju
- Department of Chemistry, School of Physical and Mathematical Sciences, University of Kerala, Thiruvananthapuram 695581, Kerala, India.
| | - G M Lekha
- Department of Chemistry, School of Physical and Mathematical Sciences, University of Kerala, Thiruvananthapuram 695581, Kerala, India.
| | - R S Aparna
- Department of Chemistry, School of Physical and Mathematical Sciences, University of Kerala, Thiruvananthapuram 695581, Kerala, India.
| | - Sony George
- Department of Chemistry, School of Physical and Mathematical Sciences, University of Kerala, Thiruvananthapuram 695581, Kerala, India.
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2
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Sayyad US, Bhatt H, Ghosh HN, Mondal S. Delineating the core and surface state heterogeneity of carbon dots during electron transfer. NANOSCALE 2024; 16:8143-8150. [PMID: 38572546 DOI: 10.1039/d4nr00271g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
Exploring the heterogeneity of carbon dots (C-Dots) is challenging because of the existence of complex structural diversity, and it is a demanding task for the development and designing of efficient C-Dots for various applications. Herein, we studied the role of the core state and surface state of C-Dots in heterogeneity via the successful investigation of the electron transfer (ET) process between different (blue, green, and red) emitting C-Dots and an electron acceptor methyl viologen (MV2+) using steady-state and time-resolved fluorescence and ultrafast transient absorption (TA) spectroscopic techniques. Selective excitation in the steady-state and time-resolved mode shows that the ET ability of the core state is higher than that of the surface state. Moreover, the kinetics of MV+˙ generation was probed using TA spectroscopy after the excitation of the core and surface state, where we observed that the surface state becomes less efficient due to the presence of an oxygen-containing functional group in the surface state, which acts as an electron scavenger. Moreover, the heterogeneity of the core and surface state was explored through the detection of the MV+˙ generation yield after the irradiation of UV and visible light (exciting the core and surface state). The result indicates that the graphitic nitrogen content in the core state and the oxygen-containing functional group in the surface state play an important role in the heterogeneity in the structure and the ET process. Our findings on the fundamental understanding of the heterogeneity of different emissive C-Dots will provide a new way of designing and developing a metal-free light-harvesting system.
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Affiliation(s)
- Umarfaruk S Sayyad
- Institute of Chemical Technology, Mumbai, Marathwada Campus, Jalna, Maharashtra 431203, India.
| | - Himanshu Bhatt
- Institute of Nano science and Technology, Mohali, Punjab 140306, India
| | - Hirendra N Ghosh
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, Odisha 752050, India
| | - Somen Mondal
- Institute of Chemical Technology, Mumbai, Marathwada Campus, Jalna, Maharashtra 431203, India.
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3
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Sousa DA, Berberan-Santos MN, Prata JV. Are "Carbon Dots" Always Carbon Dots? Evidence for their Supramolecular Nature from Structural and Dynamic Studies in Solution and in the Pure Solid. Chemistry 2024; 30:e202302955. [PMID: 37943001 DOI: 10.1002/chem.202302955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 11/06/2023] [Accepted: 11/08/2023] [Indexed: 11/10/2023]
Abstract
A model for the morphology (size, shape, and crystallinity) of carbon dots (CDs) in the solid state consistent with the observed photoluminescence in solution is proposed herein. Overwhelming evidence has been collected that links the data coming from solid-state analysis (high-resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS)) to that of solution (pulsed-field gradient (PFG)-NMR spectroscopy, time-resolved fluorescence anisotropy (TRFA), and steady-state/time-resolved fluorescence), allowing the establishment of an overall structural model for CDs. According to this model, the so-called carbon dots, observed under HRTEM imaging, are in fact supramolecular organized structures dynamically assembled from small to medium-sized molecular species when the solvent is removed to give the solid form. In this way, the imaged nanoparticles (TEM/AFM) are not covalently bound entities formed during the synthetic process, but instead supramolecular entities formed by noncovalent interactions. These particles, if at all present in solution, have the form of loose associations of relatively small molecules. This study was conducted on CDs obtained from the hydrothermal carbonization (HTC) of a biomass waste (olive wet pomace).
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Affiliation(s)
- Diogo A Sousa
- Department of Chemical Engineering Instituto Superior de Engenharia de Lisboa, Instituto Politécnico de Lisboa, 1959-007, Lisbon, Portugal
- BSIRG-iBB-Institute for Bioengineering and Biosciences, and Associate Laboratory i4HB - Institute for Health and Bioeconomy Instituto Superior Técnico, Universidade de Lisboa, 1049-001, Lisbon, Portugal
| | - Mário N Berberan-Santos
- BSIRG-iBB-Institute for Bioengineering and Biosciences, and Associate Laboratory i4HB - Institute for Health and Bioeconomy Instituto Superior Técnico, Universidade de Lisboa, 1049-001, Lisbon, Portugal
| | - José V Prata
- Department of Chemical Engineering Instituto Superior de Engenharia de Lisboa, Instituto Politécnico de Lisboa, 1959-007, Lisbon, Portugal
- CQ-VR-Centro de Química-Vila Real, Universidade de Trás-os-Montes e Alto Douro, 5001-801, Vila Real, Portugal
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4
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Langer M, Zdražil L, Medveď M, Otyepka M. Communication of molecular fluorophores with other photoluminescence centres in carbon dots. NANOSCALE 2023; 15:4022-4032. [PMID: 36728225 DOI: 10.1039/d2nr05114a] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The establishment of structure-photoluminescence (PL) relationships remains an ultimate challenge in the field of carbon dots (CDs). It is now commonly understood that various structural domains may evolve during the preparation of CDs; nonetheless, we are still far from capturing the specific features that determine the overall PL of CDs. Although the core, surface and molecular states are usually considered the three main sources of PL, it is not known to which extent they interact and/or affect one another. Expectedly, the communication between the different PL centres depends on the mutual arrangement and the type of linking. To gain insights into such a communication, time-dependent density functional theory (TD-DFT) calculations were performed for several (N-doped/O-functionalized) polyaromatic hydrocarbons (PAHs) as representative models for the core/surfaces PL states and the prototypical molecular fluorophore (MF) 5-oxo-1,2,3,5-tetrahydroimidazo-[1,2-α]-pyridine-7-carboxylic acid (IPCA), considering different interaction modes, namely hydrogen bonded and stacked complexes as well as covalently bonded and fused structures. Our results revealed that each of the studied arrangements in some way supported the communication between the PL centres. The deactivation pathways typically involve multiple charge and energy transfer events that can promote the formation of charge separated states and/or lead to the activation of other PL centres in CDs. Depending on the arrangement, the doping pattern and surface functionalization, both the CD core and the MF can act as an electron donor or acceptor, which could help to design CDs with desirable hole-electron surface/core characteristics.
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Affiliation(s)
- Michal Langer
- Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute (CATRIN), Palacký University Olomouc, Šlechtitelů 241/27, 783 71 Olomouc, Czech Republic.
- Chemical and Biological Systems Simulation Lab, Centre of New Technologies University of Warsaw, 2c Banacha Street, 02-097, Warszawa, Poland
| | - Lukáš Zdražil
- Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute (CATRIN), Palacký University Olomouc, Šlechtitelů 241/27, 783 71 Olomouc, Czech Republic.
| | - Miroslav Medveď
- Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute (CATRIN), Palacký University Olomouc, Šlechtitelů 241/27, 783 71 Olomouc, Czech Republic.
- Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 974 01 Banská Bystrica, Slovak Republic
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute (CATRIN), Palacký University Olomouc, Šlechtitelů 241/27, 783 71 Olomouc, Czech Republic.
- IT4Innovations, VŠB-Technical University of Ostrava, 17. listopadu 2172/15, 708 00 Ostrava-Poruba, Czech Republic
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5
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Crista D, Algarra M, Martínez de Yuso MV, Esteves da Silva JCG, Pinto da Silva L. Investigation of the role of pH and the stoichiometry of the N-dopant in the luminescence, composition and synthesis yield of carbon dots. J Mater Chem B 2023; 11:1131-1143. [PMID: 36637160 DOI: 10.1039/d2tb02318k] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Carbon dots (CDs) are carbon-based nanoparticles with very attractive luminescence features, which simplicity and flexibility of their fabrication can lead to an endless number of CDs with distinct properties and applications. High fluorescence quantum yields (QYFL) are generally a necessary feature for various applications of CDs. One commonly employed strategy to improve the fluorescence properties of CDs is heteroatom-doping using precursors containing desired heteroatoms (with focus on N-doping). In this work, we report the synthesis and systematic investigation of an array of N-doped CDs, obtained from the dry heating of solid mixtures of glucose and urea in different molar ratios with two main objectives: to study the role of stoichiometry in the optical properties and composition of CDs and to investigate the formation of possible alkaline-responsive nanoparticles and the potential of this procedure for obtaining CDs with higher synthesis yields. We have characterized the optical properties of this diverse array of glucose and urea-based CDs using both UV-Vis and fluorescence spectroscopies. In addition, we have also examined the CDs by using high-resolution transmission electron microscopy (HR-TEM) and X-Ray photoelectron (XPS) spectroscopy, as well as by assessing the thermal stability of the nanoparticles. We have found that this fabrication process generates two types of CDs, one readily soluble in water and other only soluble at basic pH. The latter was characterized by higher synthesis yields, and lower QYFL and thermal stability, when compared with those of the former. Furthermore, the stoichiometry of the N-dopant does not appear to be correlated with the QYFL of the obtained CDs. This study provides novel information that should be useful for the future rational development of CDs with higher QYFL and synthesis yields.
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Affiliation(s)
- Diana Crista
- Chemistry Research Unit (CIQUP), Institute of Molecular Sciences (IMS), Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences, University of Porto, R. Campo Alegre s/n, 4169-007 Porto, Portugal.
| | - Manuel Algarra
- INAMAT2-Institute for Advanced Materials and Mathematics, Department of Science, Public University of Navarra, Campus of Arrosadía, 31006 Pamplona, Spain.
| | - Maria Valle Martínez de Yuso
- X-ray Photoelectron Spectroscopy Lab. Central Service to Support Research Building (SCAI), University of Málaga, 29071 Málaga, Spain
| | - Joaquim C G Esteves da Silva
- Chemistry Research Unit (CIQUP), Institute of Molecular Sciences (IMS), Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences, University of Porto, R. Campo Alegre s/n, 4169-007 Porto, Portugal. .,LACOMEPHI, GreenUPorto, Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences, University of Porto, R. Campo Alegre s/n, 4169-007 Porto, Portugal
| | - Luís Pinto da Silva
- Chemistry Research Unit (CIQUP), Institute of Molecular Sciences (IMS), Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences, University of Porto, R. Campo Alegre s/n, 4169-007 Porto, Portugal. .,LACOMEPHI, GreenUPorto, Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences, University of Porto, R. Campo Alegre s/n, 4169-007 Porto, Portugal
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6
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Ghorai N, Bhunia S, Burai S, Ghosh HN, Purkayastha P, Mondal S. Ultrafast insights into full-colour light-emitting C-Dots. NANOSCALE 2022; 14:15812-15820. [PMID: 36255011 DOI: 10.1039/d2nr04642c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Designing carbon dots (C-Dots) in a controlled way requires a profound understanding of their photophysical properties, such as the origin of their fluorescence and excitation wavelength-dependent emission properties, which has been a perennial problem in the last few decades. Herein, we synthesized three different C-Dots (blue, green, and red-emitting C-Dots) from the same starting materials via a hydrothermal method and separated them by silica column chromatography. All the purified C-Dots exhibited three different emission maxima after a certain range of different excitations, showing a high optical uniformity in their emission properties. It was also observed that the average distributions of the particle size in all the C-Dots were the same with a typical size of 4 nm and the same interplanar d spacing of ∼0.21 nm. Here, we tried to establish a well-defined conclusive answer to the puzzling optical properties of C-Dots via successfully investigating the carrier dynamics of their core and surface state with a myriad use of steady-state, time-resolved photoluminescence, and ultrafast transient absorbance spectroscopy techniques. The ultrafast charge-carrier dynamics of the core and surface state clearly indicated that the graphitic nitrogen in the core state and the oxygen-containing functional group in the surface state predominately contribute to controlling their wide range of emission properties. We believe that these findings will give the C-Dots their own designation in the fluorophore world and create a new avenue for designing and developing C-Dot-based new architectures.
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Affiliation(s)
- Nandan Ghorai
- Institute of Nano Science and Technology, Mohali, Punjab 140306, India
| | - Soumyadip Bhunia
- Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, WB, India
| | - Subham Burai
- Institute of Chemical Technology, Mumbai, Marathwada Campus, Jalna, Maharashtra 431203, India.
| | - Hirendra N Ghosh
- Institute of Nano Science and Technology, Mohali, Punjab 140306, India
- Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Pradipta Purkayastha
- Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, WB, India
| | - Somen Mondal
- Institute of Chemical Technology, Mumbai, Marathwada Campus, Jalna, Maharashtra 431203, India.
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7
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Kasprzyk W, Świergosz T, Romańczyk PP, Feldmann J, Stolarczyk JK. The role of molecular fluorophores in the photoluminescence of carbon dots derived from citric acid: current state-of-the-art and future perspectives. NANOSCALE 2022; 14:14368-14384. [PMID: 36156633 DOI: 10.1039/d2nr03176k] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Carbon dots (CDs), an emerging class of nanomaterials, have attracted considerable attention due to their intriguing photophysical properties. Despite their indisputable potential of utilization in many fascinating areas of research and life, some fundamental aspects concerning their structure and the origin of their photoluminescence (PL) properties still await clarification. The mechanism of PL emission of CDs is associated with their structure, which is dependent on the carbonization process. At the initial stages of CD synthesis via a bottom-up approach, molecular fluorophores are considered to dominate the optical characteristics of the resulting nanomaterials. In this review, the recent progress in the use of molecular state theory for explanation of the structure-property relationship in CDs is summarized. This review focuses exclusively on the molecular fluorophores existing in nanomaterials prepared from citric acid (CA) as one of the most frequent carbon sources reported for the bottom-up synthesis of CDs. Consequently, the most relevant transformations of CA and the history of molecular fluorophores derived from it are described, followed by an in-depth discussion on their relevance in understanding the specific photophysical properties of blue-, green-, and red-emitting CDs. Finally, the challenging issues and future perspectives of molecular state PL mechanism exploration in CDs are highlighted.
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Affiliation(s)
- Wiktor Kasprzyk
- Department of Biotechnology and Physical Chemistry, Faculty of Chemical Engineering and Technology, Cracow University of Technology, Warszawska 24, 31-155 Kraków, Poland.
| | - Tomasz Świergosz
- Department of Chemical Technology and Environmental Analysis, Faculty of Chemical Engineering and Technology, Cracow University of Technology, Warszawska 24, 31-155 Kraków, Poland
| | - Piotr P Romańczyk
- Department of Biotechnology and Physical Chemistry, Faculty of Chemical Engineering and Technology, Cracow University of Technology, Warszawska 24, 31-155 Kraków, Poland.
| | - Jochen Feldmann
- Chair for Photonics and Optoelectronics, Nano-Institute Munich, Department of Physics, Ludwig-Maximilians-Universität München, Königinstrasse 10, Munich, 80539, Germany
| | - Jacek K Stolarczyk
- Chair for Photonics and Optoelectronics, Nano-Institute Munich, Department of Physics, Ludwig-Maximilians-Universität München, Königinstrasse 10, Munich, 80539, Germany
- Smoluchowski Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
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8
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Astafiev AA, Shakhov AM, Tskhovrebov AG, Shatov A, Gulin A, Shepel D, Nadtochenko VA. Nitrogen-Doped Carbon Nanodots Produced by Femtosecond Laser Synthesis for Effective Fluorophores. ACS OMEGA 2022; 7:6810-6823. [PMID: 35252675 PMCID: PMC8892850 DOI: 10.1021/acsomega.1c06413] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 02/03/2022] [Indexed: 06/04/2023]
Abstract
Understanding the effect of heteroatom doping is crucial for the design of carbon nanodots (CNDs) with enhanced luminescent properties for fluorescence imaging and light-emitting devices. Here, we study the effect and mechanisms of luminescence enhancement through nitrogen doping in nanodots synthesized by the bottom-up route in an intense femtosecond laser field using the comparative analysis of CNDs obtained from benzene and pyridine. We demonstrate that laser irradiation of aromatic compounds produces hybrid nanoparticles consisting of a nanocrystalline core with a shell of surface-bonded aromatic rings. These nanoparticles exhibit excitation-dependent visible photoluminescence typical for CNDs. Incorporation of nitrogen into pyridine-derived CNDs enhances their luminescence characteristics through the formation of small pyridine-based fluorophores peripherally bonded to the nanoparticles. We identify oxidation of surface pyridine rings as a mechanism of formation of several distinct blue- and green-emitting fluorophores in nanodots, containing pyridine moieties. These findings shed additional light on the nature and formation mechanism of effective fluorophores in nitrogen-doped carbon nanodots produced by the bottom-up route.
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Affiliation(s)
- Artyom A. Astafiev
- Bio&Nanophotonics
Lab, N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russian Federation
- Chemistry
Department, Moscow State University, 119991 Moscow, Russian Federation
| | - Aleksander M. Shakhov
- Bio&Nanophotonics
Lab, N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russian Federation
- Chemistry
Department, Moscow State University, 119991 Moscow, Russian Federation
| | - Alexander G. Tskhovrebov
- Bio&Nanophotonics
Lab, N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russian Federation
- Research
Institute of Chemistry, People’s
Friendship University of Russia, 117198 Moscow, Russian Federation
| | - Alexander Shatov
- Bio&Nanophotonics
Lab, N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russian Federation
| | - Alexander Gulin
- Bio&Nanophotonics
Lab, N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russian Federation
| | - Denis Shepel
- Bio&Nanophotonics
Lab, N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russian Federation
| | - Victor A. Nadtochenko
- Bio&Nanophotonics
Lab, N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russian Federation
- Chemistry
Department, Moscow State University, 119991 Moscow, Russian Federation
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9
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De CK, Ghosh A, Mandal PK. Hydrophobicity-Dependent Heterogeneous Nanoaggregates and Fluorescence Dynamics in Room-Temperature Ionic Liquids. J Phys Chem B 2022; 126:1551-1557. [PMID: 35166544 DOI: 10.1021/acs.jpcb.1c08598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The hydrophobicity of room-temperature ionic liquids (RTILs) has been shown to have a very significant effect on the optical and structural properties of and in RTILs. The average excited state lifetime of neat RTILs has been shown to be increasing with increasing hydrophobicity of the RTILs. By employing pico-nanosecond-based fluorescence anisotropy decay, the volume of the nanoaggregates in neat RTILs have been calculated. The volume of these nanoaggregates have been shown to be decreasing with increase in hydrophobicity of the RTILs. Thus, hydrophobicity has been shown to have an important role, i.e., hydrophobicity can be used as a handle to tune the properties of RTILs as designer solvents. Moreover, the excited-state lifetime of red-emitting fluorophores, i.e., whose fluorescence emission is not perturbed by the inherent emission of RTILs, has been shown to increase with the increasing hydrophobicity of the RTILs. Highly hydrophobic RTILs have been shown to exhibit positive deviation and highly hydrophilic RTIL has been shown to exhibit negative deviation from the linear correlation between average solvation time (τs) versus viscosity/temperature (η/T).
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10
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Bhuyan R, Bramhaiah K, Bhattacharyya S. Specific locations of blue and green-emitting units in dual emissive carbon dots and their reversible emitting properties due to switchable inter-chromophoric interactions. J Colloid Interface Sci 2021; 605:364-372. [PMID: 34332410 DOI: 10.1016/j.jcis.2021.07.119] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 07/03/2021] [Accepted: 07/22/2021] [Indexed: 12/14/2022]
Abstract
Carbon dots (CDs) are the unique class of luminescent nanomaterials consist of various chromophoric units heterogeneously distributed throughout the nanoparticle, resulting intriguing multistate emissive properties. Herein, we have critically investigated the specific locations of the blue and green-emitting centers inside dual emissive CDs by steady-state and time-resolved polarized emission study. It is further clarified by a temperature-dependent fluorescence study for both the emitting domains. Results suggest that the blue chromophoric units are located at the interior part of CDs, while green units are mostly at the exterior region. Furthermore, we have investigated the solvent-dependent inter-chromophoric interactions between the two emissive domains by the Time-Resolved Area Normalized Emission Spectroscopy (TRANES). Results suggest that at polar aprotic solvent acetone, time-dependent positive evolution of green-emitting states and negative evolution of blue emissive domains have been observed. This reversible emitting properties evolve due to the excited state energy migration from blue emissive domains to green emissive domains at polar aprotic medium, while in the case of polar protic solvent water, this phenomenon is missing. This switchable inter-chromophoric interaction are correlated further with the inter-particle interactions of CDs.
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Affiliation(s)
- Rahul Bhuyan
- Indian Institute of Science Education and Research, Govt. ITI Building (transit campus), Engg. School Road, Berhampur, Odisha 760010 India
| | - Kommula Bramhaiah
- Indian Institute of Science Education and Research, Govt. ITI Building (transit campus), Engg. School Road, Berhampur, Odisha 760010 India
| | - Santanu Bhattacharyya
- Indian Institute of Science Education and Research, Govt. ITI Building (transit campus), Engg. School Road, Berhampur, Odisha 760010 India.
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11
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Tsai IH, Li JT, Chang CW. Effects of Sonication and Hydrothermal Treatments on the Optical and Chemical Properties of Carbon Dots. ACS OMEGA 2021; 6:14174-14181. [PMID: 34124440 PMCID: PMC8190798 DOI: 10.1021/acsomega.1c00765] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 05/12/2021] [Indexed: 06/12/2023]
Abstract
In our study, we have tested the effects of sonication and hydrothermal treatments on the properties of carbon dots synthesized from a microwave-assisted method (C-dotsMW). When the carbon dots are sonicated in an aerobic environment, the fluorescence quantum yield decreases drastically because the molecular fluorophores attached to the surface of the carbon dots are oxidized during the sonication process. Meanwhile, the sonicated C-dotsMW also lose their Hg2+ ion sensing and photoreduction activity due to the oxidization of surface functional groups. After the hydrothermal treatment, the fluorescence quantum yield of C-dotsMW increases due to the formation of new fluorophores; however, the Hg2+ ion sensitivity and photoreduction activity of C-dotsMW decrease significantly due to the oxidization of surface functional groups. By autoclaving the C-dotsMW at 100 °C, we have demonstrated that we can enhance the fluorescence quantum yield of C-dotsMW without losing their Hg2+ ion sensitivity. This finding can be used to improve the fluorescence quantum yield of the fluorescent ion sensor based on C-dots.
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Affiliation(s)
- I-Hua Tsai
- Department of Chemistry, National Changhua University of Education, No. 1 Jin-De Road, Changhua City 50058, Taiwan
| | - Jyun-Ting Li
- Department of Chemistry, National Changhua University of Education, No. 1 Jin-De Road, Changhua City 50058, Taiwan
| | - Chih-Wei Chang
- Department of Chemistry, National Changhua University of Education, No. 1 Jin-De Road, Changhua City 50058, Taiwan
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12
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Ragazzon G, Cadranel A, Ushakova EV, Wang Y, Guldi DM, Rogach AL, Kotov NA, Prato M. Optical processes in carbon nanocolloids. Chem 2021. [DOI: 10.1016/j.chempr.2020.11.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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13
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Akhuli A, Chakraborty D, Agrawal AK, Sarkar M. Probing the Interaction of Bovine Serum Albumin with Copper Nanoclusters: Realization of Binding Pathway Different from Protein Corona. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:1823-1837. [PMID: 33502208 DOI: 10.1021/acs.langmuir.0c03176] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
With an aim to understand the interaction mechanism of bovine serum albumin (BSA) with copper nanoclusters (CuNCs), three different types CuNCs having chemically different surface ligands, namely, tannic acid (TA), chitosan, and cysteine (Cys), have been fabricated, and investigations are carried out in the absence and presence of protein (BSA) at ensemble-averaged and single-molecule levels. The CuNCs, capped with different surface ligands, are consciously chosen so that the role of surface ligands in the overall protein-NCs interactions is clearly understood, but, more importantly, to find whether these CuNCs can interact with protein in a new pathway without forming the "protein corona", which otherwise has been observed in relatively larger nanoparticles when they are exposed to biological fluids. Analysis of the data obtained from fluorescence, ζ-potential, and ITC measurements has clearly indicated that the BSA protein in the presence of CuNCs does not attain the binding stoichiometry (BSA/CuNCs > 1) that is required for the formation of "protein corona". This conclusion is further substantiated by the outcome of the fluorescence correlation spectroscopy (FCS) study. Further analysis of data and thermodynamic calculations have revealed that the surface ligands of the CuNCs play an important role in the protein-NCs binding events, and they can alter the mode and thermodynamics of the process. Specifically, the data have demonstrated that the binding of BSA with TA-CuNCs and Chitosan-CuNCs follows two types of binding modes; however, the same with Cys-CuNCs goes through only one type of binding mode. Circular dichroism (CD) measurements have indicated that the basic structure of BSA remains almost unaltered in the presence of CuNCs. The outcome of the present study is expected to encourage and enable better application of NCs in biological applications.
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Affiliation(s)
- Amit Akhuli
- School of Chemical Sciences, National Institute of Science Education and Research, HBNI, Bhimpur-Padanpur, Jatni, Khorda, Bhubaneswar 752050, Odisha, India
| | - Debabrata Chakraborty
- School of Chemical Sciences, National Institute of Science Education and Research, HBNI, Bhimpur-Padanpur, Jatni, Khorda, Bhubaneswar 752050, Odisha, India
| | - Aman Kumar Agrawal
- School of Chemical Sciences, National Institute of Science Education and Research, HBNI, Bhimpur-Padanpur, Jatni, Khorda, Bhubaneswar 752050, Odisha, India
| | - Moloy Sarkar
- School of Chemical Sciences, National Institute of Science Education and Research, HBNI, Bhimpur-Padanpur, Jatni, Khorda, Bhubaneswar 752050, Odisha, India
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Rahaman SA, Sahid Hossain M, Hatai J, Bandyopadhyay S. Energy Relay Enhances Switching Efficiency in a Dendrimer–Azobenzene Supramolecular Assembly with an Anion–π Motif. CHEMPHOTOCHEM 2020. [DOI: 10.1002/cptc.202000209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Sk. Atiur Rahaman
- Department of Chemical Sciences Indian Institute of Science Education and Research (IISER) Kolkata Mohanpur, Nadia, West Bengal 741246 India
| | - Munshi Sahid Hossain
- Department of Chemical Sciences Indian Institute of Science Education and Research (IISER) Kolkata Mohanpur, Nadia, West Bengal 741246 India
| | - Joydev Hatai
- Institute of Organic Chemistry University of Duisburg-Essen Universitätsstraße 745141 Essen Germany
| | - Subhajit Bandyopadhyay
- Department of Chemical Sciences Indian Institute of Science Education and Research (IISER) Kolkata Mohanpur, Nadia, West Bengal 741246 India
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Wang Y, Wang L, Wang H. Investigation on the Relationship Between Carbon Cores and Fluorescence Moieties by Measurement of Fluorescence Anisotropy of CDs with Different Sizes. Chem Res Chin Univ 2020. [DOI: 10.1007/s40242-020-9109-2] [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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16
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Evaluation of Different Bottom-up Routes for the Fabrication of Carbon Dots. NANOMATERIALS 2020; 10:nano10071316. [PMID: 32635483 PMCID: PMC7407658 DOI: 10.3390/nano10071316] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/26/2020] [Accepted: 07/02/2020] [Indexed: 02/07/2023]
Abstract
Carbon dots (CDs) are carbon-based nanoparticles with very attractive luminescence features. Furthermore, their synthesis by bottom-up strategies is quite flexible, as tuning the reaction precursors and synthesis procedures can lead to an endless number of CDs with distinct properties and applications. However, this complex variability has made the characterization of the structural and optical properties of the nanomaterials difficult. Herein, we performed a systematic evaluation of the effect of three representative bottom-up strategies (hydrothermal, microwave-assisted, and calcination) on the properties of CDs prepared from the same precursors (citric acid and urea). Our results revealed that these synthesis routes led to nanoparticles with similar sizes, identical excitation-dependent blue-to-green emission, and similar surface-functionalization. However, we have also found that microwave and calcination strategies are more efficient towards nitrogen-doping than hydrothermal synthesis, and thus, the former routes are able to generate CDs with significantly higher fluorescence quantum yields than the latter. Furthermore, the different synthesis strategies appear to have a role in the origin of the photoluminescence of the CDs, as hydrothermal-based nanoparticles present an emission more dependent on surface states, while microwave- and calcination-based CDs present an emission with more contributions from core states. Furthermore, calcination and microwave routes are more suitable for high-yield synthesis (~27-29%), while hydrothermal synthesis present almost negligible synthesis yields (~2%). Finally, life cycle assessment (LCA) was performed to investigate the sustainability of these processes and indicated microwave synthesis as the best choice for future studies.
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Islam MM, Barik S, Preeyanka N, Sarkar M. Interaction of Lysozyme with Monocationic and Dicationic Ionic Liquids: Toward Finding a Suitable Medium for Biomacromolecules. J Phys Chem B 2020; 124:961-973. [DOI: 10.1021/acs.jpcb.9b10270] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mullah Muhaiminul Islam
- School of Chemical Sciences, National Institute of Science Education and Research, Bhubaneswar, HBNI, Bhimpur-Padanpur,
Jatni, Khurda, Bhubaneswar 752050, Odisha, India
| | - Sahadev Barik
- School of Chemical Sciences, National Institute of Science Education and Research, Bhubaneswar, HBNI, Bhimpur-Padanpur,
Jatni, Khurda, Bhubaneswar 752050, Odisha, India
| | - Naupada Preeyanka
- School of Chemical Sciences, National Institute of Science Education and Research, Bhubaneswar, HBNI, Bhimpur-Padanpur,
Jatni, Khurda, Bhubaneswar 752050, Odisha, India
| | - Moloy Sarkar
- School of Chemical Sciences, National Institute of Science Education and Research, Bhubaneswar, HBNI, Bhimpur-Padanpur,
Jatni, Khurda, Bhubaneswar 752050, Odisha, India
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Starukhin AN, Nelson DK, Eurov DA, Kurdyukov DA, Golubev VG. Manifestation of fluorophore segmental motion in carbon dots in steady-state fluorescence experiments. Phys Chem Chem Phys 2020; 22:8401-8408. [DOI: 10.1039/d0cp00056f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Perrin plot of carbon dots in aqueous glycerol solutions of different viscosity at T = 298 K.
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Abstract
Unexpectedly bright photoluminescence emission can be observed in materials incorporating inorganic carbon when their size is reduced from macro–micro to nano. At present, there is no consensus in its understanding, and many suggested explanations are not consistent with the broad range of experimental data. In this Review, I discuss the possible role of collective excitations (excitons) generated by resonance electronic interactions among the chromophore elements within these nanoparticles. The Förster-type resonance energy transfer (FRET) mechanism of energy migration within nanoparticles operates when the composing fluorophores are the localized electronic systems interacting at a distance. Meanwhile, the resonance interactions among closely located fluorophores may lead to delocalization of the excited states over many molecules resulting in Frenkel excitons. The H-aggregate-type quantum coherence originating from strong coupling among the transition dipoles of adjacent chromophores in a co-facial stacking arrangement and exciton transport to emissive traps are the basis of the presented model. It can explain most of the hitherto known experimental observations and must stimulate the progress towards their versatile applications.
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Sendão RMS, Crista DMA, Afonso ACP, Martínez de Yuso MDV, Algarra M, Esteves da Silva JCG, Pinto da Silva L. Insight into the hybrid luminescence showed by carbon dots and molecular fluorophores in solution. Phys Chem Chem Phys 2019; 21:20919-20926. [PMID: 31517344 DOI: 10.1039/c9cp03730f] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Carbon dots have attracted great attention from the research community given their very attractive luminescent properties. However, the recent discovery that some of these properties may result from fluorescent impurities originating from the synthesis process, and not from the carbon dots themselves, constitute a significant setback to our knowledge of these materials. Herein, we proceeded to the study of carbon dots generated from citric acid and urea via a microwave-assisted synthesis, focusing on their analysis by AFM, HR-TEM, XPS, FT-IR, ESI-MS, UV-Vis and fluorescence spectroscopy. We have found that this synthesis process does generate molecular fluorophores that can mask the luminescence of the carbon dots. More importantly, our data demonstrates that when present in the same solution, the carbon dots and these fluorophores do not behave as separated species with individual emission. Instead, they interact to produce a hybrid luminescence, which excited state properties and reactivity are different from the properties of the individual species. These results indicate the possibility for the development of hybrid materials composed by carbon dots and related molecular fluorophores with new and improved properties.
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Affiliation(s)
- Ricardo M S Sendão
- Chemistry Research Unit (CIQUP), Faculty of Sciences of University of Porto, R. Campo Alegre 697, 4169-007 Porto, Portugal
| | - Diana M A Crista
- Chemistry Research Unit (CIQUP), Faculty of Sciences of University of Porto, R. Campo Alegre 697, 4169-007 Porto, Portugal
| | - Ana Carolina P Afonso
- Chemistry Research Unit (CIQUP), Faculty of Sciences of University of Porto, R. Campo Alegre 697, 4169-007 Porto, Portugal
| | - Maria Del Valle Martínez de Yuso
- X-Ray Photoelectron Spectroscopy Lab, Central Service to Support Research Bulding (SCAI), University of Málaga, 29071 Málaga, Spain
| | - Manuel Algarra
- CQM-Centro de Química da Madeira, Universidade da Madeira, Campus da Penteada, 9020-105 Funchal, Portugal
| | - Joaquim C G Esteves da Silva
- Chemistry Research Unit (CIQUP), Faculty of Sciences of University of Porto, R. Campo Alegre 697, 4169-007 Porto, Portugal and LACOMEPHI, GreenUPorto, Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences of University of Porto, R. Campo Alegre 697, 4169-007 Porto, Portugal.
| | - Luís Pinto da Silva
- Chemistry Research Unit (CIQUP), Faculty of Sciences of University of Porto, R. Campo Alegre 697, 4169-007 Porto, Portugal and LACOMEPHI, GreenUPorto, Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences of University of Porto, R. Campo Alegre 697, 4169-007 Porto, Portugal.
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Das A, Roy D, De CK, Mandal PK. Reply to the 'Comment on ""Where does the fluorescing moiety reside in a carbon dot?"- Investigations based on fluorescence anisotropy decay and resonance energy transfer dynamics"' by H. C. Joshi, Phys. Chem. Chem. Phys., 2019, 21, DOI: 10.1039/c9cp00136k. Phys Chem Chem Phys 2019; 21:13370-13373. [PMID: 31168554 DOI: 10.1039/c9cp01668f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The claim that the analysis regarding resonance energy transfer should have been made using different equations than those that we have used is negated based on the following points: (1) we are well aware of the equations the author has provided in his comment. The equation (eqn (3) mentioned below) that the author has written is undoubtedly too simple to describe the complex system delineated in our original paper. This particular equation is perhaps OK for simple dye (donor and acceptor) systems; however, such a simple equation is never enough for nanoparticle/quantum dot systems. (2) Another equation suggested by the author in his comment (eqn (2)) contains a parameter called donor concentration in excited state. We have categorically described in page 6-7 of our original paper why it is difficult to measure the donor concentration accurately even in the ground state. When the donor concentration can't be known accurately it can't be used in the suggested equation. (3) Donor-acceptor distance calculated by eqn (3)/Table 1 provided by the author deviates more than 100% from the distance that is physically feasible. Such kinds of problems are well documented in the literature. (4) One of the papers cited by the author in his comment and many other published papers clearly mention that in the case when all donor molecules/particles do not take part in the resonance energy transfer process or the stoichiometry of a donor-acceptor complex is not known or deviates strongly from 1 : 1, especially in quantum dots or any other nanomaterial system, it is not possible to extract accurate dynamical information related to RET from donor decay. Instead risetime of acceptor yields much more accurate information. Such situations do arise in our system as 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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Joshi HC. Comment on ""Where does the fluorescing moiety reside in a carbon dot?"- Investigations based on fluorescence anisotropy decay and resonance energy transfer dynamics" by A. Das, D. Roy, C. K. De and P. K. Mandal, Phys. Chem. Chem. Phys., 2018, 20, 2251. Phys Chem Chem Phys 2019; 21:13368-13369. [PMID: 31155619 DOI: 10.1039/c9cp00136k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In a recent paper published in Physical Chemistry Chemical Physics (Phys. Chem. Chem. Phys., 2018, 20, 2251-2259), Förster resonance energy transfer (FRET) between carbon dots and rhodamine 123 has been reported. The FRET rates and hence donor acceptor distances estimated from acceptor rise time for various acceptor concentrations appear to be incorrect. In the present comment need for a correct analysis in the case of such a scenario is addressed.
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Affiliation(s)
- Hem C Joshi
- Institute for Plasma Research, Bhat, Gandhinagar-382428, India.
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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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