Publications in International Journals

1. P. Ghosh, S.S. Jaffer, T. Das, A. Maity, D. Kumar, and P. Purkayastha, Solvatochromic study of three indoloquinoline derivatives: Effect of chloro group/s on the photophysics of the compounds, (communicated).
2. S.S. Jaffer, P. Ghosh, A. Das, and P. Purkayastha, Opening of DNA double helix at room temperature: Application of α-cyclodextrin self-aggregates, Nanoscale (in press)
3. P. Purkayastha, Cu2+ induced charge transfer switch by choosing the right cyclodextrin environment, J. Photochem. Photobiol. A: Chem. (in press).
4. S.S. Jaffer, and P. Purkayastha, Steady state fluorescence spectroscopic technique revealing the thermodynamics of fragmentation of compound induced α-cyclodextrin nanotubular suprastructures, J. Colloid Interface Sci. 342, 2010, 57-61.
5. M. Sowmiya, P. Purkayastha, A. Tiwari, S.S. Jaffer, and S.K. Saha, Characterization of guest molecule concentration dependent nanotubes of β-cyclodextrin and their secondary assembly: Study of trans-2-[4-(dimethylamino)styryl] benzothiazole, a TICT-fluorescent probe, J. Photochem. Photobiol. A: Chem. 205, 2009, 186-196.
6. S.S. Jaffer, S.K. Saha, and P. Purkayastha, Fragmentation of Molecule-Induced g-cyclodextrin Nanotubular Suprastructures Due to Drug Dosage, J. Colloid Interface Sci. 337, 2009, 294-299. 
7. P. Purkayastha, Formation of compound induced nanotubular suprastructure by cyclodextrins: Application as a molecular carrier, Green Technology, 8, 2009, 60-65.
8. S.K. Saha, P. Purkayastha, and A.B. Das, Photophysical characterization and effect of pH on the twisted intramolecular charge transfer fluorescence of trans-2-[4-(dimethylamino)styryl] benzothiazole, J. Photochem. Photobiol. A: Chem., 195, 2008, 368-377.
9. A. Chakrabarty, P. Purkayastha, and N. Chattopadhyay, Laser Induced Optoacoustic Spectroscopy of Benzil: Evaluation of Structural Volume Change upon Photoisomerization, J. Photochem. Photobiol. A: Chem., 198, 2008, 256-261.
10. S.S. Jaffer, M. Sowmiya, S.K. Saha, and P. Purkayastha, Defining the different phases of premicellar aggregation using the photophysical changes of a surface probing compound, J. Colloid Interface Sci., 325, 2008, 236-242.
11. S.S. Jaffer, S.K. Saha, G. Eranna, A.K. Sharma, and P. Purkayastha, Intramolecular charge transfer probe induced formation of a-cyclodextrin nanotubular suprastructures: A concentration dependent process, J. Phys. Chem. C, 112, 2008, 11199-11204.
12. S.K. Saha, P. Purkayastha, A.B. Das, and S. Dhara, Excited state isomerization and effect of viscosity and temperature dependent torsional relaxation on TICT fluorescence of trans-2-[4-(dimethylamino) styryl]benzothiazole, J. Photochem. Photobiol. A: Chem., 199, 2008, 179-187.
13. P. Purkayastha, D. Das, and S.S. Jaffer, Cyclic voltammetry as a tool to study the nature of cyclodextrin encapsulation: application to nanotubular suprastructure formation, J. Mol. Struct., 892, 2008, 461-465. 
14. A. Chakraborty, A. Mallick, B. Haldar, P. Purkayastha, P. Das and N. Chattopadhyay, Surfactant Chain length Dependent Modulation of Prototropic Transformation of a Biological Photosensitizer: Norharmane in Anionic Micelles, Langmuir, 23, 2007, 4842-4848.
15. P. Das, A. Mallick, P. Purkayastha, B. Haldar and N. Chattopadhyay, Fluorescence resonance energy transfer from TX-100 to 3-acetyl-4-oxo-6,7dihydro-12H-indolo-[2,3-a]quinolizine in premicellar and micellar environments, J. Mol. Liq., 130, 2007, 48-51.
16. A. Mallick, P. Purkayastha, and N. Chattopadhyay, Photoprocesses of excited molecules in confined liquid environments: An overview, J. Photochem. Photobiol. C: Photochem. Rev., 8, 2007, 109-127.
17. Y. Xu, P. Purkayastha, and F. Gai, Nanosecond folding dynamics of a three-stranded b-sheet, J. Am. Chem. Soc., 128, 2006, 15836-15842.
18. P. Purkayastha and J. Tang, Coupling of a conventional spectrofluorimeter with stopped-flow devices: A simple way to get a stopped-flow fluorescence set-up, Instrumentation Science and Technology, 34, 2006, 555-565.
19. P. Purkayastha, J. W. Klemke, S. Lavender, R. Oyola, B. Cooperman, and F. Gai, α1-antitrypsin polymerization: a fluorescence correlation spectroscopic study, Biochemistry, 44, 2005, 2642-2649.
20. B. Haldar, A. Mallick, P. Purkayastha, H. D. Burrows and N. Chattopadhyay, Differential encapsulation of pyrene-end-capped poly(ethylene oxide) by cyclodextrins in aqueous solutions. A fluorometric study, Indian J. Chem. A, 43, 2004, 2265-2273.
21. P. Purkayastha and N. Chattopadhyay, Theoretical Modeling for the Ground State Rotamerization and Excited State Intramolecular Proton Transfer of 2-(2¢-hydroxyphenyl)oxazole, 2-(2¢-hydroxyphenyl)imidazole, 2-(2¢-hydroxyphenyl)thiazole and Their Benzo Analogues, Int. J. Mol. Sci. 4, 2003, 335-361.
22. S. Sengupta and P. Purkayastha, A tetraphenylmethane based dendritic tolan anthracene dyad: synthesis and energy transfer properties, Org. Biomol. Chem., 1, 2003, 436-440.
23. A. Mallick, S. Maiti, B. Haldar, P. Purkayastha and N. Chattopadhyay, Photophysics of 3-acetyl-4-oxo-6,7-dihydro-12H indolo-[2,3-a] quinolizine: emission from two states, Chem. Phys. Lett., 371, 2003, 688-693.
24. D.A. Tocher, M.G.B. Drew, S. Chowdhury, P. Purkayastha and D. Datta, Mixed ligand binuclear copper (I) complexes containing CuI2N8 chromophores. Observation of emission from MLCT excited states involving two different ligands, Indian J. Chem., 42A, 2003, 484.
25. P. Purkayastha and N. Chattopadhyay, Rotamerisation and intramolecular proton transfer of 2-(2'-hydroxyphenyl)oxazole, 2-(2'-hydroxyphenyl)imidazole and 2-(2'-hydroxyphenyl) thiazole: A theoretical study; J. Mol. Struct., 604, 2002, 87-99.
26. P. Purkayastha and N. Chattopadhyay, Photoluminescence of 2 - (2'- hydroxy-5'-methylbenzoyl) -1,5- diphenylpyrrole in aqueous and beta-cyclodextrin environments: manifestation of open and closed conformers; J. Mol. Struct., 570, 2001, 145-152.
27. N. Chattopadhyay, C. Serpa, P. Purkayastha, L. G. Arnaut and S. J. Formosinho, Photocyclization of triphenylamine: an investigation through time-resolved photoacoustic calorimetry; Phys. Chem. Chem. Phys., 3, 2001, 70-73.
28. P. Purkayastha, S. C. Bera and N. Chattopadhyay Ground and excited state Proton transfer of some carbazole derivatives : A linear correlation between the acidity constant and charge density on the deprotonation centre, J. Mol. Liq., 88/1, 2000, 33-42. 
29. D. Sur, P. Purkayastha and N. Chattopadhyay Photophysics of 1H-1,5-benzo diazepine in aqueous cyclodextrin envionments; Indian J. Chem. A, 39, 2000,389. 
30. P. Purkayastha and N. Chattopadhyay Role of rotamerization and excited state intramolecular proton transfer in the photophysics of 2-(2'-hydroxyphenyl) benzoxazole, 2-(2'-hydroxyphenyl) benzimidazole and 2-(2'-hydroxyphenyl) benzthiazole : A theoretical Study; Phys. Chem. Chem. Phys., 2, 2000, 203-210. 
31. P. Purkayastha, N. Chattopadhyay, G. K. Patra and D. Datta, Metal ion induced enhancement of emission of an organic fluorophore; Indian J. Chem. A, 39, 2000,375. 
32. D. Sur, P. Purkayastha and N. Chattopadhyay, Kinetics of photoconversion of diphenylamine in beta-cyclodextrin environment; J. Photochem. Photobiol. A: Chem., 134, 2000, 17-21. 
33. D. Sur, P. Purkayastha, S. C. Bera, P. K. Bhattacharyya and N. Chattopadhyay, Effect of cyclodextrin encapsulation on the photocyclization of diphenylamine: cavity imposed steric restriction on the reaction rate; J. Mol. Liq., 89, 2000, 175-188. 
34. P. K. Pal, S. Chowdhury, P. Purkayastha, D. A. Toecher and D. Datta, A novel double-stranded dinuclear copper(I) helicate having a photoluminescent CuI2N8 chromophore; Inorg. Chem. Comm., 3, 2000, 585-589. 
35. P. Purkayastha, P. K. Bhattacharyya, S. C. Bera, and N. Chattopadhyay, Intersystem crossing (ISC) in DMABN and DMABA : Laser induced optoacoustic spectroscopy and semiempirical (AM1) calculations; Phys. Chem. Chem. Phys., 1, 1999, 3253-3258.