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Chowdhury A, Goswami S. Study of Drug Delivery Using Purely Organic Macrocyclic Containers-Cucurbit[7]uril and Pillararene. ACS OMEGA 2023; 8:47340-47366. [PMID: 38144095 PMCID: PMC10733925 DOI: 10.1021/acsomega.3c05465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 11/10/2023] [Accepted: 11/20/2023] [Indexed: 12/26/2023]
Abstract
An impaired immune system is the root of various human ailments provoking the urge to find vehicle-mediated quick delivery of small drug molecules and other vital metabolites to specific tissues and organs. Thus, drug delivery strategies are in need of improvement in therapeutic efficacy. It can be achieved only by increasing the drug-loading capacity, increasing the sustained release of a drug to its target site, easy relocation of drug molecules associated with facile complexation-induced properties of molecular vehicles, and high stimuli-responsive drug administration. Supramolecular drug delivery systems (SDDS) provide a much needed robust yet facile platform for fabricating innovative drug nanocarriers assembled by thermodynamically noncovalent interaction with the tunable framework and above-mentioned properties. Measures of cytotoxicity and biocompatibility are the two main criteria that lie at the root of any promising medicinal applications. This Review features significant advancements in (i) supramolecular host-guest complexation using cucurbit[7]uril (CB[7]), (ii) encapsulation of the drug and its delivery application tailored for CB[7], (iii) self-assembly of supramolecular amphiphiles, (iv) supramolecular guest relay using host-protein nanocavities, (v) pillararene (a unique macrocyclic host)-mediated SDDS for the delivery of smart nanodrugs for siRNA, fluorescent molecules, and insulin for juvenile diabetes. Furthermore, fundamental questions and future hurdles related to smart SDDS based on CB[7] and pillararenes and their future promising breakthrough implementations are also distinctly outlined in this Review.
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Affiliation(s)
- Arnab
Roy Chowdhury
- Department of Chemistry, Amity
University Kolkata, Kolkata, West Bengal 700135, India
| | - Soumyabrata Goswami
- Department of Chemistry, Amity
University Kolkata, Kolkata, West Bengal 700135, India
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2
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Alzard RH, Bufaroosha MS, Al-Shamsi N, Sohail A, Al-Dubaili N, Salem AA, Abdou IM, Saleh N. Solubilization of Pyridone-Based Fluorescent Tag by Complexation in Cucurbit[7]uril. ACS OMEGA 2019; 4:953-960. [PMID: 31459370 PMCID: PMC6648827 DOI: 10.1021/acsomega.8b02761] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 12/27/2018] [Indexed: 06/10/2023]
Abstract
Aimed at further exploring the hosting properties of cucurbit[7]uril (CB7), we have exploited the spectroscopic and photophysical properties of a known fluorescent label as the guest molecule, namely, 3-cyano-6-(2-thienyl)-4-trifluoromethyl pyridine (TFP), in neat solvents. The formation of an inclusion host-guest complex with CB7 was checked by UV-vis absorption spectroscopy, and the value of binding constant (9.7 × 105 M-1) was extracted from the spectrophotometric data. The modulation of keto-enol equilibrium in TFP by the local environment is governed by the interplay between dimerization through intermolecular hydrogen bonding between individual solute molecules, favoring the enol form, and intermolecular hydrogen bonding between TFP and the surrounding solvents, favoring the keto form. Time-resolved fluorescence results established that the macromolecular CB7 host stabilizes preferentially the neutral enol form over the keto form of TFP. Unprecedentedly, our results reveal a linear dependence of the amplitudes of the extracted decay-associated spectra from the time-resolved fluorescence spectra of TFP on the sum of polarity/polarizability and hydrogen bonding parameters of the local environment, confirming that TFP at micromolar concentration in the CB7 complexes is experiencing a methanol-like environment. The results rationalized the 42-fold enhancement in the solubility of TFP in water media by complexation in CB7.
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3
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Behera SK, Pegu M, Krishnamoorthy G. Modulation of Twisted Intramolecular Charge Transfer Emission of 2-(4′- N,N
-Dimethylaminophenyl)imidazopyridines in Aqueous Cucurbit[7]uril +. ChemistrySelect 2018. [DOI: 10.1002/slct.201703074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Santosh Kumar Behera
- Department of Chemistry; Indian Institute of Technology Guwahati-781039; India Assam
| | - Meenakshi Pegu
- Department of Chemistry; Indian Institute of Technology Guwahati-781039; India Assam
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4
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Sappati S, Hassanali A, Gebauer R, Ghosh P. Nuclear quantum effects in a HIV/cancer inhibitor: The case of ellipticine. J Chem Phys 2017; 145:205102. [PMID: 27908111 DOI: 10.1063/1.4968046] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Ellipticine is a natural product that is currently being actively investigated for its inhibitory cancer and HIV properties. Here we use path-integral molecular dynamics coupled with excited state calculations to characterize the role of nuclear quantum effects on the structural and electronic properties of ellipticine in water, a common biological solvent. Quantum effects collectively enhance the fluctuations of both light and heavy nuclei of the covalent and hydrogen bonds in ellipticine. In particular, for the ellipticine-water system, where the proton donor and acceptor have different proton affinities, we find that nuclear quantum effects (NQEs) strengthen both the strong and the weak H bonds. This is in contrast to what is observed for the cases where the proton affinity of the donors and acceptors is same. These structural fluctuations cause a significant red-shift in the absorption spectra and an increase in the broadening, bringing it into closer agreement with the experiments. Our work shows that nuclear quantum effects alter both qualitatively and quantitatively the optical properties of this biologically relevant system and highlights the importance of the inclusion of these effects in the microscopic understanding of their optical properties. We propose that isotopic substitution will produce a blue shift and a reduction in the broadening of the absorption peak.
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Affiliation(s)
- Subrahmanyam Sappati
- Department of Chemistry, Indian Institute of Science Education and Research, Pune 411008, India
| | - Ali Hassanali
- Condensed Matter and Statistical Physics Section, The Abdus Salam International Centre for Theoretical Physics, I-34151 Trieste, Italy
| | - Ralph Gebauer
- Condensed Matter and Statistical Physics Section, The Abdus Salam International Centre for Theoretical Physics, I-34151 Trieste, Italy
| | - Prasenjit Ghosh
- Department of Chemistry, Indian Institute of Science Education and Research, Pune 411008, India
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5
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Becher J, Berdnikova DV, Dzubiel D, Ihmels H, Pithan PM. Interactions between photoacidic 3-hydroxynaphtho[1,2- b]quinolizinium and cucurbit[7]uril: Influence on acidity in the ground and excited state. Beilstein J Org Chem 2017; 13:203-212. [PMID: 28228861 PMCID: PMC5301965 DOI: 10.3762/bjoc.13.23] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 01/16/2017] [Indexed: 02/05/2023] Open
Abstract
3-Hydroxynaphtho[1,2-b]quinolizinium was synthesized by cyclodehydration route and its optical properties in different media were investigated. The absorption and emission spectra of this compound depend on the pH of the solution. Thus, at higher pH values the deprotonation yields a merocyanine-type dye that exhibits significantly red-shifted absorption bands and causes a dual emisson, i.e., a combination of emission bands of the hydroxyquinolizinium and its deprotonated form. Whereas this compound is a weak acid in the ground state (pKa = 7.9), it has a strongly increased acidity in the excited state (pKa* = 0.4). As a result, the blue-shifted fluorescence of the hydroxyquinolizinium becomes dominant only under strongly acidic conditions. In addition, it is shown that 3-hydroxynaphtho[1,2-b]quinolizinium binds to cucurbit[7]uril (CB[7]) with moderate affinity (Kb = 1.8 × 104 M-1, pH 5) and that the pKa and pKa* values of this ligand increase by about two to three orders of magnitude, respectively, when bound to CB[7].
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Affiliation(s)
- Jonas Becher
- Department of Chemistry and Biology, University of Siegen and Center of Micro- and Nanochemistry and Engineering, Adolf-Reichwein-Str. 2, 57068 Siegen, Germany
| | - Daria V Berdnikova
- Department of Chemistry and Biology, University of Siegen and Center of Micro- and Nanochemistry and Engineering, Adolf-Reichwein-Str. 2, 57068 Siegen, Germany
| | - Darinka Dzubiel
- Department of Chemistry and Biology, University of Siegen and Center of Micro- and Nanochemistry and Engineering, Adolf-Reichwein-Str. 2, 57068 Siegen, Germany
| | - Heiko Ihmels
- Department of Chemistry and Biology, University of Siegen and Center of Micro- and Nanochemistry and Engineering, Adolf-Reichwein-Str. 2, 57068 Siegen, Germany
| | - Phil M Pithan
- Department of Chemistry and Biology, University of Siegen and Center of Micro- and Nanochemistry and Engineering, Adolf-Reichwein-Str. 2, 57068 Siegen, Germany
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6
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Koninti RK, Palvai S, Satpathi S, Basu S, Hazra P. Loading of an anti-cancer drug into mesoporous silica nano-channels and its subsequent release to DNA. NANOSCALE 2016; 8:18436-18445. [PMID: 27775145 DOI: 10.1039/c6nr06285g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Mesoporous silica nano-channel (MCM-41) based molecular switching of a biologically important anticancer drug, namely, ellipticine (EPT) has been utilized to probe its efficient loading onto MCM-41, and its subsequent release to intra-cellular biomolecules, like DNA. By exploiting various spectroscopic techniques (like, steady state fluorescence, time-resolved fluorescence and circular dichroism), it has been shown that EPT can be easily translocated from MCM-41 to DNA without using any external stimulant. Blue emission of EPT in a polar aprotic solvent, i.e., dichloromethane (DCM), completely switches to green upon loading inside MCM-41 due to the conversion from a neutral to a protonated form of the drug inside nano-pores. Powder X-ray diffraction (PXRD), N2 gas adsorption and confocal fluorescence microscopy results confirm the adsorption of EPT inside the nano-pores of MCM-41. Here, the lysozyme (Lyz) protein has been utilized as a pore blocker of MCM-41 in order to prevent premature drug release. Interestingly, EPT is released to DNA even from the EPT-MCM-Lyz composite system, and results in intensification of green fluorescence. Electron microscopy results reveal the formation of a distinctive garland kind of morphology involving MCM-41 and DNA probably through non-covalent interactions, and this is believed to be responsible for the DNA assisted release of drug molecules from silica nano-pores. Confocal laser scanning microscopy (CLSM) imaging revealed that EPT-MCM is successfully internalized into the HeLa cervical cancer cells and localized into the nucleus. Cell viability assay results infer that EPT-MCM and EPT-MCM-Lyz showed much improved efficacy in HeLa cancer cells compared to free ellipticine.
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Affiliation(s)
- Raj Kumar Koninti
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Maharashtra, India.
| | - Sandeep Palvai
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Maharashtra, India.
| | - Sagar Satpathi
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Maharashtra, India.
| | - Sudipta Basu
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Maharashtra, India.
| | - Partha Hazra
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Maharashtra, India.
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7
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Ganguly A, Ghosh S, Guchhait N. Inclusion of an Anthracene-based Fluorophore within Molecular Containers: A Comparative Study of the Cucurbituril and Cyclodextrin Host Families. J Phys Chem B 2016; 120:4421-30. [PMID: 27119387 DOI: 10.1021/acs.jpcb.6b04178] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this paper, the binding interaction of a promising chloride channel blocker, 9-methyl anthroate (9-MA), with two different classes of molecular containers, β-cyclodextrins (β-CD and methyl-β-CD) and cucurbit[7]uril, having comparable cavity dimensions, has been thoroughly demonstrated via inspection of the modulation of the excited-state properties of the emissive molecule. Spectral data suggest that CB7 encapsulates the probe more efficiently in a 1:2 fashion, whereas the efficacies of β-CDs are relatively less and the corresponding stoichiometry is 1:1. Interestingly, despite being thermodynamically much more favorable than the probe-β-CD complexation equilibria, the fraction of probe-CB7 complex formed is appreciably smaller with respect to that of probe-β-CD complexes. This apparent inconsistency has been addressed via the proposition that since the formation of a 1:2 complex is entropically disadvantageous, it is anticipated that the activation barrier of the corresponding reaction is reasonably high, and thus only a small fraction of the reactants are able to surpass the energy barrier to form the products. This proposition has been thoroughly corroborated by fluorescence lifetime measurements at different temperatures.
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Affiliation(s)
- Aniruddha Ganguly
- Department of Chemistry, University of Calcutta , 92 Acharya Prafulla Chandra Road, Calcutta 700009, India
| | - Soumen Ghosh
- Department of Chemistry, University of Calcutta , 92 Acharya Prafulla Chandra Road, Calcutta 700009, India
| | - Nikhil Guchhait
- Department of Chemistry, University of Calcutta , 92 Acharya Prafulla Chandra Road, Calcutta 700009, India
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8
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Miskolczy Z, Biczók L, Jablonkai I. Multiple inclusion complex formation of protonated ellipticine with cucurbit[8]uril: thermodynamics and fluorescence properties. Supramol Chem 2016. [DOI: 10.1080/10610278.2016.1174237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Zsombor Miskolczy
- Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - László Biczók
- Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - István Jablonkai
- Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
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9
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Koninti RK, Sappati S, Satpathi S, Gavvala K, Hazra P. Spectroscopy and Dynamics of Cryptolepine in the Nanocavity of Cucurbit[7]uril and DNA. Chemphyschem 2016; 17:506-15. [PMID: 26650669 DOI: 10.1002/cphc.201501011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Revised: 12/07/2015] [Indexed: 02/03/2023]
Affiliation(s)
- Raj Kumar Koninti
- Department of Chemistry; Indian Institute of Science Education and Research (IISER); Pune 411008 Maharashtra India
| | - Subrahmanyam Sappati
- Department of Chemistry; Indian Institute of Science Education and Research (IISER); Pune 411008 Maharashtra India
| | - Sagar Satpathi
- Department of Chemistry; Indian Institute of Science Education and Research (IISER); Pune 411008 Maharashtra India
| | - Krishna Gavvala
- Department of Chemistry; Indian Institute of Science Education and Research (IISER); Pune 411008 Maharashtra India
| | - Partha Hazra
- Department of Chemistry; Indian Institute of Science Education and Research (IISER); Pune 411008 Maharashtra India
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10
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Miskolczy Z, Biczók L, Jablonkai I. The origin of the dual fluorescence of protonated ellipticine in water. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2015.12.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Chandra F, Pal K, Lathwal S, Koner AL. Supramolecular guest relay using host-protein nanocavities: an application of host-induced guest protonation. MOLECULAR BIOSYSTEMS 2016; 12:2859-66. [DOI: 10.1039/c6mb00423g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Small drug molecules and other important metabolites are delivered via a suitable carrier protein-mediated transport through a specific receptor.
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Affiliation(s)
- Falguni Chandra
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal
- India
| | - Kaushik Pal
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal
- India
| | - Sushil Lathwal
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal
- India
| | - Apurba L. Koner
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal
- India
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12
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Saleh N, Al-Handawi MB, Bufaroosha MS, Assaf KI, Nau WM. Tuning protonation states of tripelennamine antihistamines by cucurbit[7]uril. J PHYS ORG CHEM 2015. [DOI: 10.1002/poc.3504] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Na'il Saleh
- Chemistry Department, College of Science; United Arab Emirates University; Al-Ain United Arab Emirates
| | - Marieh B. Al-Handawi
- Chemistry Department, College of Science; United Arab Emirates University; Al-Ain United Arab Emirates
| | - Muna S. Bufaroosha
- Chemistry Department, College of Science; United Arab Emirates University; Al-Ain United Arab Emirates
| | - Khaleel I. Assaf
- Department of Life Sciences and Chemistry; Jacobs University Bremen; Campus Ring 1 D-28759 Bremen Germany
| | - Werner M. Nau
- Department of Life Sciences and Chemistry; Jacobs University Bremen; Campus Ring 1 D-28759 Bremen Germany
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13
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Gavvala K, Koninti RK, Sengupta A, Hazra P. Excited state proton transfer dynamics of an eminent anticancer drug, ellipticine, in octyl glucoside micelle. Phys Chem Chem Phys 2015; 16:14953-60. [PMID: 24931633 DOI: 10.1039/c4cp01783h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Photophysics and proton transfer dynamics of an eminent anticancer drug, ellipticine (EPT), have been investigated inside a biocompatible octyl-β-D-glucoside (OBG) micellar medium using steady state and time-resolved fluorescence spectroscopic techniques. EPT exists as protonated form in aqueous solution of pH 7. When EPT molecules are encapsulated in OBG micelles, protonated form is converted to neutral form in the ground state due to the hydrophobic effect of the micellar environment. Interestingly, steady state fluorescence results indicate the existence of both neutral and protonated forms of EPT in the excited state, even though neutral molecules are selectively excited, and it is attributed to the conversion of neutral to protonated form of EPT by the excited state proton transfer (ESPT) process. A clear isoemissive point in the time-resolved area normalized emission spectra (TRANES) further supports the excited state conversion of neutral to protonated form of EPT. Notably, this kind of proton transfer dynamics is not observed in other conventional micelles, such as, SDS, Triton-X and CTAB. Therefore, the observed ESPT dynamics is believed to be an outcome of combined effects of the local dielectric constant felt by EPT and the local proton concentration at the OBG micellar surface.
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Affiliation(s)
- Krishna Gavvala
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune-411008, Maharashtra, India.
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14
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Gavvala K, Satpathi S, Hazra P. Ultrafast dynamics of a molecular rotor in chemical and biological nano-cavities. RSC Adv 2015. [DOI: 10.1039/c5ra13298c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Excited state dynamics of CCVJ are investigated inside the nano-cavities of CD and HSA using steady-state and femtosecond up-conversion techniques.
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Affiliation(s)
- Krishna Gavvala
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER)
- Pune 411008
- India
| | - Sagar Satpathi
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER)
- Pune 411008
- India
| | - Partha Hazra
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER)
- Pune 411008
- India
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15
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Gavvala K, Satpathi S, Hazra P. pH responsive translocation of an anticancer drug between cyclodextrin and DNA. RSC Adv 2015. [DOI: 10.1039/c5ra19839a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Herein, the pH triggered translocation of EPT in between γ-cyclodextrin and DNA is monitored using fluorescence switch of the drug.
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Affiliation(s)
- Krishna Gavvala
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER)
- Pune 411008
- India
| | - Sagar Satpathi
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER)
- Pune 411008
- India
| | - Partha Hazra
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER)
- Pune 411008
- India
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16
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Sengupta A, Singh RK, Gavvala K, Koninti RK, Mukherjee A, Hazra P. Urea induced unfolding dynamics of flavin adenine dinucleotide (FAD): spectroscopic and molecular dynamics simulation studies from femto-second to nanosecond regime. J Phys Chem B 2014; 118:1881-90. [PMID: 24456234 DOI: 10.1021/jp412339a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Here, we investigate the effect of urea in the unfolding dynamics of flavin adenine dinucleotide (FAD), an important enzymatic cofactor, through steady state, time-resolved fluorescence spectroscopic and molecular dynamics (MD) simulation studies. Steady state results indicate the possibility of urea induced unfolding of FAD, inferred from increasing emission intensity of FAD with urea. The TCSPC and up-conversion results suggest that the stack-unstack dynamics of FAD severely gets affected in the presence of urea and leads to an increase in the unstack conformation population from 15% in pure water to 40% in 12 M urea. Molecular dynamics simulation was employed to understand the nature of the interaction between FAD and urea at the molecular level. Results depict that urea molecules replace many of the water molecules around adenine and isoalloxazine rings of FAD. However, the major driving force for the stability of this unstack conformations arises from the favorable stacking interaction of a significant fraction of the urea molecules with adenine and isoalloxazine rings of FAD, which overcomes the intramolecular stacking interaction between themselves observed in pure water.
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Affiliation(s)
- Abhigyan Sengupta
- Department of Chemistry, Indian Institute of Science Education and Research (IISER)-Pune , Pune (411008), Maharashtra, India
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17
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Gavvala K, Koninti RK, Sengupta A, Hazra P. Cucurbit[7]uril assisted ultraviolet to visible fluorescence switch of a heart medicine. Phys Chem Chem Phys 2014; 16:2823-6. [DOI: 10.1039/c3cp54895c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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