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Sengupta A, Khade RV, Hazra P. How Does the Urea Dynamics Differ from Water Dynamics inside the Reverse Micelle? J Phys Chem A 2011; 115:10398-407. [DOI: 10.1021/jp206069z] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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52
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Agarkar SA, Kulkarni RR, Dhas VV, Chinchansure AA, Hazra P, Joshi SP, Ogale SB. Isobutrin from butea monosperma (flame of the forest): a promising new natural sensitizer belonging to chalcone class. ACS APPLIED MATERIALS & INTERFACES 2011; 3:2440-2444. [PMID: 21608995 DOI: 10.1021/am200341y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this work, "isobutrin", an ecofriendly sensitizer that is extracted from Butea monosperma (commonly known as "Flame of the Forest") flowers, is introduced. It is a bright yellow pigment belonging to the chalcone class and is examined as a sensitizer for optoelectronic applications. It is observed that chelation of this dye with Ti ions results into a strong dye-TiO(2) charge transfer (DTCT) band in the visible region. This Ti-Isobutrin chelate is stable, irreversible and its formation is studied using Benesi-Hildebrand plot. The locations of HOMO-LUMO states of the Ti-isobutrin chelate and the corresponding band alignment with TiO(2) are obtained. Also, a thermal stability test revealed that isobutrin is stable above 100 °C.
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Sengupta A, Khade RV, Hazra P. pH dependent dynamic behavior of flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) in femtosecond to nanosecond time scale. J Photochem Photobiol A Chem 2011. [DOI: 10.1016/j.jphotochem.2011.04.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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54
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Sengupta A, Hazra P. Solvation dynamics of Coumarin 153 in SDS dispersed single walled carbon nanotubes (SWNTs). Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.10.049] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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55
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Hazra P, Adhikary L, Dave N, Khedkar A, Manjunath HS, Anantharaman R, Iyer H. Development of a process to manufacture PEGylated orally bioavailable insulin. Biotechnol Prog 2010; 26:1695-704. [DOI: 10.1002/btpr.487] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 07/05/2010] [Indexed: 11/08/2022]
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Bhattacharya A, Mazumdar D, Das AK, Hazra P, Pal S. Peroxidase and Polyphenoloxidase Activities and Phenol Content in Fruit of Eggplant and Their Relationship to Infestation by Shoot and Fruit Borer. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/19315260903000495] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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57
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Kannan V, Narayanaswamy P, Gadamsetty D, Hazra P, Khedkar A, Iyer H. A tandem mass spectrometric approach to the identification of O-glycosylated glargine glycoforms in active pharmaceutical ingredient expressed in Pichia pastoris. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2009; 23:1035-1042. [PMID: 19253914 DOI: 10.1002/rcm.3965] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Glycoforms of glargine expressed in Pichia pastoris were isolated by high-performance liquid chromatography and analyzed by a series of chemical and mass spectrometric methods for the identification of various glycoforms, glycosylation position, nature and structure of glycans. Reduction and alkylation, peptide mapping techniques were used to decipher the amino acid site at which glycosylation had taken place. Chemical methods were coupled with mass spectrometry techniques such as electrospray ionization and matrix-assisted laser desorption/ionization for identification of the glycosylation site.
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Hazra P, Inoue K, Laan W, Hellingwerf KJ, Terazima M. Energetics and role of the hydrophobic interaction during photoreaction of the BLUF domain of AppA. J Phys Chem B 2008; 112:1494-501. [PMID: 18189382 DOI: 10.1021/jp0767314] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A recently developed method for time-resolved thermodynamic measurements was used to study the photochemical reaction(s) of the BLUF domain of AppA (AppA-BLUF), which has a dimeric form in the ground state, in terms of the energetics and heat capacity changes (DeltaC(p)) in different time domains. The enthalpy change (DeltaH) of the first intermediate that forms within 1 ns after photoexcitation was 38 (+/-8) kJ mol(-1) at 298 K. The heat capacity change (DeltaC(p)) upon formation of this intermediate was positive [1.4 (+/-0.3) kJ mol(-1) K(-1)]. This positive DeltaC(p) suggests that the hydrophobic surface area of AppA-BLUF exposed to the bulk solvent increased. After this initial transition, a dimerization reaction with another ground-state dimer (i.e., tetramer formation) takes place. Upon this reaction, the energy was stabilized to 26 (+/-6) kJ mol(-1) at 298 K. Interestingly, the dimer formation was accompanied by a larger but negative DeltaC(p) [-6.0 (+/-1) kJ mol(-1) K(-1)]. This negative DeltaC(p) might indicate buried hydrophobic residues at the interface of the dimer and/or the existence of trapped water at the interface. We suggest that hydrophobic interactions are the main driving force for the formation of the dimer upon photoactivation of AppA-BLUF.
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Dave N, Hazra P, Khedkar A, Manjunath HS, Iyer H, Suryanarayanan S. Process and purification for manufacture of a modified insulin intended for oral delivery. J Chromatogr A 2007; 1177:282-6. [PMID: 17675047 DOI: 10.1016/j.chroma.2007.07.036] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Revised: 07/12/2007] [Accepted: 07/17/2007] [Indexed: 11/19/2022]
Abstract
Oral delivery of insulin is convenient and physiologically desirable in the treatment of diabetes. However, this route of administration has presented substantial challenges as insulin is degraded enzymatically in the gut, resulting in low bioavailability. We have developed a conjugated insulin product (IN-105) that has high bioavailability and is currently undergoing clinical trials for the treatment of diabetes. A process for the manufacture of IN-105 was developed. Initially, recombinant human insulin was conjugated covalently with a monodisperse, short-chain methoxypolyethylene glycol derivative. The desired product, IN-105, was purified from its closely related species using RP-HPLC and cation exchange chromatography to a purity of 98.5%. The elution pool from cation exchange chromatography was crystallized and lyophilized into the dry active pharmaceutical ingredient.
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Hazra P, Inoue K, Laan W, Hellingwerf KJ, Terazima M. Tetramer formation kinetics in the signaling state of AppA monitored by time-resolved diffusion. Biophys J 2006; 91:654-61. [PMID: 16648173 PMCID: PMC1483092 DOI: 10.1529/biophysj.106.083915] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The photoreaction kinetics of the BLUF domain of AppA(5-125) was studied by monitoring time-dependence of an apparent diffusion coefficient (D) using the pulsed laser-induced transient grating technique. It was found that D of the photoproduct is time-dependent. From the concentration dependence of the reaction rate, it was concluded that the BLUF domain of AppA forms a dimer upon the photoexcitation. Since AppA exists as a dimeric form in the ground state, this dimerization reaction indicates the tetramer formation in the signaling state. From the slope of the plot of observed rate constants (k(obs)) against the AppA concentration, the second order rate constant is determined to be approximately 2.5 x 10(5) M(-1) s(-1), which is approximately 4 orders in magnitude lower than the diffusion controlled reaction. It indicates that a relative orientation of the protein molecules during the dimerization process causes additional constraints, which slow down the reaction rate.
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Chakraborty A, Chakrabarty D, Seth D, Hazra P, Sarkar N. Photo-induced intermolecular electron transfer from electron donating solvents to Coumarin dyes in bile salt aggregates: role of diffusion in electron transfer reaction. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2006; 63:594-602. [PMID: 16027032 DOI: 10.1016/j.saa.2005.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2005] [Revised: 05/18/2005] [Accepted: 06/04/2005] [Indexed: 05/03/2023]
Abstract
The photo-induced electron transfer between Coumarin dyes and aromatic amines has been investigated using steady state and time-resolved fluorescence quenching studies. We have observed a Marcus type inversion in the electron transfer rate in correlation of quenching constant to the free energy change occurred during reaction. To justify the "inverted region" obtained in the correlation of quenching constant versus free energy curve, we have performed anisotropy measurement and estimated the several diffusional parameters. The translational diffusion coefficients exhibit a similar picture like electron transfer rate constant when it is plotted against free energy. Thus we argued that the diffusion has played an important role in the electron transfer kinetics.
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Chakrabarty D, Chakraborty A, Seth D, Hazra P, Sarkar N. Binding and relaxation behavior of Coumarin-153 in lecithin–taurocholate mixed micelles: A time resolved fluorescence spectroscopic study. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.06.098] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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63
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Chakrabarty D, Chakraborty A, Seth D, Hazra P, Sarkar N. Effect of alkyl chain length and size of the headgroups of the surfactant on solvent and rotational relaxation of Coumarin 480 in micelles and mixed micelles. J Chem Phys 2005; 122:184516. [PMID: 15918738 DOI: 10.1063/1.1895722] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The effect of alkyl chain length and size of the headgroups of the surfactant on the solvation dynamics and rotational relaxation of Coumarin 480 (C-480) has been investigated using dynamic Stokes' shift of C-480 in different types of alkyltrimethylammonium bromide micelles and mixed micelles. The rotational relaxation time increases with increase in alkyl chain length of the surfactant. The increase in the number of alkyl chains of the surfactant leads to the more close packed micelles, hence the microviscosity of the micelles increases and consequently rotational relaxation time increases. Solvation time also increases due to the increase in number of alkyl chains of the surfactant. The change in solvation and rotational relaxation time is more prominent in micelles compared to mixed micelles. The solvation and rotational relaxation time also increase with the increase in size of the headgroup of the surfactant.
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Chakraborty A, Seth D, Chakrabarty D, Hazra P, Sarkar N. Photoinduced electron transfer from dimethyl aniline to coumarin dyes in reverse micelles. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.01.099] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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65
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Chakrabarty D, Chakraborty A, Hazra P, Seth D, Sarkar N. Dynamics of photoisomerisation and rotational relaxation of 3,3′-diethyloxadicarbocyanine iodide in room temperature ionic liquid and binary mixture of ionic liquid and water. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.08.109] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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66
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Chakrabarty D, Chakraborty A, Seth D, Hazra P, Sarkar N. Dynamics of solvation and rotational relaxation of Coumarin 153 in 1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6]–water mixtures. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.08.141] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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67
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Hazra P, Chakrabarty D, Chakraborty A, Sarkar N. Effect of hydrogen bonding on intramolecular charge transfer in aqueous and non-aqueous reverse micelles. J Photochem Photobiol A Chem 2004. [DOI: 10.1016/j.jphotochem.2004.04.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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68
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Chakrabarty D, Hazra P, Chakraborty A, Sarkar N. Dynamics of solvation and rotational relaxation in neutral Brij 35 and Brij 58 micelles. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.05.084] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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69
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Hazra P, Chakrabarty D, Chakraborty A, Sarkar N. Intramolecular charge transfer and solvation dynamics of Nile Red in the nanocavity of cyclodextrins. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.02.078] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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70
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Chakraborty A, Chakrabarty D, Hazra P, Seth D, Sarkar N. Corrigendum to: `Photoinduced intermolecular electron transfer between Coumarin dyes and electron donating solvents in cetyltrimethylammonium bromide (CTAB) micelles: evidence for Marcus inverted region' [Chem. Phys. Lett. 382 (2003) 508]. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.02.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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71
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Hazra P, Chakrabarty D, Chakraborty A, Sarkar N. Probing protein-surfactant interaction by steady state and time-resolved fluorescence spectroscopy. Biochem Biophys Res Commun 2004; 314:543-9. [PMID: 14733941 DOI: 10.1016/j.bbrc.2003.12.118] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The microenvironment of the probe coumarin 153 (C-153) in 1% bovine serum albumin (BSA) is more hydrophobic in nature compared to that in pure micelles or protein-surfactant complexes. In the native state of protein, we have not observed any solvation using C-153 as a probe but we have observed a slow dynamics on protein surface using 8-anilino-1-naphthalenesulfonic acid (ANS) as a probe. This may be due to the location of the probe (C-153) in the hydrophobic, solvent-inaccessible pocket of the BSA. Solvation dynamics in the BSA-surfactant (SDS) complexes in the solution phase is markedly different from that in pure micelles. This is may be due to the formation of 'necklace and bead' structure in the complexes. The rotational motion is also severely hindered in the surface of the protein.
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Chakraborty A, Chakrabarty D, Hazra P, Seth D, Sarkar N. Photoinduced intermolecular electron transfer between Coumarin dyes and electron donating solvents in cetyltrimethylammonium bromide (CTAB) micelles: evidence for Marcus inverted region. Chem Phys Lett 2003. [DOI: 10.1016/j.cplett.2003.10.105] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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73
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Chakrabarty D, Hazra P, Chakraborty A, Sarkar N. Solvation Dynamics of Coumarin 480 in Bile Salt−Cetyltrimethylammonium Bromide (CTAB) and Bile Salt−Tween 80 Mixed Micelles. J Phys Chem B 2003. [DOI: 10.1021/jp0360467] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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74
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Chakrabarty D, Hazra P, Chakraborty A, Seth D, Sarkar N. Dynamics of solvent relaxation in room temperature ionic liquids. Chem Phys Lett 2003. [DOI: 10.1016/j.cplett.2003.10.029] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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75
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Chakrabarty D, Hazra P, Sarkar N. Solvation Dynamics of Coumarin 480 in TritonX-100 (TX-100) and Bile Salt Mixed Micelles. J Phys Chem A 2003. [DOI: 10.1021/jp0271458] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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76
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Hazra P, Chakrabarty D, Sarkar N. Solvation dynamics of Coumarin 153 in aqueous and non-aqueous reverse micelles. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(03)00304-x] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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77
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Hazra P, Chakrabarty D, Sarkar N. Solvation dynamics of Coumarin 152A in methanol and acetonitrile reverse micelles. Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)00679-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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78
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Hazra P, Sarkar N. Solvation dynamics of Coumarin 490 in methanol and acetonitrile reverse micelles. Phys Chem Chem Phys 2002. [DOI: 10.1039/b109447e] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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79
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Hazra P, Sarkar N. Intramolecular charge transfer processes and solvation dynamics of coumarin 490 in reverse micelles. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)00595-4] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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