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di Nunzio MR, Gutiérrez M, Moreno JM, Corma A, Díaz U, Douhal A. Interrogating the Behaviour of a Styryl Dye Interacting with a Mesoscopic 2D-MOF and Its Luminescent Vapochromic Sensing. Int J Mol Sci 2021; 23:ijms23010330. [PMID: 35008756 PMCID: PMC8745538 DOI: 10.3390/ijms23010330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/21/2021] [Accepted: 12/23/2021] [Indexed: 12/14/2022] Open
Abstract
In this contribution, we report on the solid-state-photodynamical properties and further applications of a low dimensional composite material composed by the luminescent trans-4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) dye interacting with a two-dimensional-metal organic framework (2D-MOF), Al-ITQ-HB. Three different samples with increasing concentration of DCM are synthesized and characterized. The broad UV-visible absorption spectra of the DCM/Al-ITQ-HB composites reflect the presence of different species of DCM molecules (monomers and aggregates). In contrast, the emission spectra are narrower and exhibit a bathochromic shift upon increasing the DCM concentration, in agreeance with the formation of adsorbed aggregates. Time-resolved picosecond (ps)-experiments reveal multi-exponential behaviors of the excited composites, further confirming the heterogeneous nature of the samples. Remarkably, DCM/Al-ITQ-HB fluorescence is sensitive to vapors of electron donor aromatic amine compounds like aniline, methylaniline, and benzylamine due to a H-bonding-induced electron transfer (ET) process from the analyte to the surface-adsorbed DCM. These findings bring new insights on the photobehavior of a well-known dye when interacting with a 2D-MOF and its possible application in sensing aniline derivatives.
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Affiliation(s)
- Maria Rosaria di Nunzio
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Av. Carlos III, s/n, 45071 Toledo, Spain; (M.R.d.N.); (M.G.)
| | - Mario Gutiérrez
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Av. Carlos III, s/n, 45071 Toledo, Spain; (M.R.d.N.); (M.G.)
| | - José María Moreno
- Instituto de Tecnología Química, Universitat Politécnica de Valéncia-Consejo Superior de Investigaciones Científicas (UPV-CSIC), Av. de los Naranjos, s/n, 46022 Valencia, Spain; (J.M.M.); (A.C.); (U.D.)
| | - Avelino Corma
- Instituto de Tecnología Química, Universitat Politécnica de Valéncia-Consejo Superior de Investigaciones Científicas (UPV-CSIC), Av. de los Naranjos, s/n, 46022 Valencia, Spain; (J.M.M.); (A.C.); (U.D.)
| | - Urbano Díaz
- Instituto de Tecnología Química, Universitat Politécnica de Valéncia-Consejo Superior de Investigaciones Científicas (UPV-CSIC), Av. de los Naranjos, s/n, 46022 Valencia, Spain; (J.M.M.); (A.C.); (U.D.)
| | - Abderrazzak Douhal
- Departamento de Química Física, Facultad de Ciencias Ambientales y Bioquímica, and INAMOL, Universidad de Castilla-La Mancha, Av. Carlos III, s/n, 45071 Toledo, Spain; (M.R.d.N.); (M.G.)
- Correspondence:
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Aslam J, Hussain Lone I, Ansari F, Aslam A, Aslam R, Akram M. Molecular binding interaction of pyridinium based gemini surfactants with bovine serum albumin: Insights from physicochemical, multispectroscopic, and computational analysis. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 250:119350. [PMID: 33387804 DOI: 10.1016/j.saa.2020.119350] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/10/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
To study the interaction of the series of pyridinium based gemini surfactants (GS) (referred to as m-Py-m, m = 14, 16); 4,4'-(propane-1,3-diyl)bis(1-(2-(tetradecyloxy)-2-oxoethyl) dipyridinium chloride (14-Py-14), and 4,4'-(propane-1,3-diyl) bis(1-(2-(hexadecyloxy)-2-oxoethyl)dipyridinium chloride (16-Py-16) with bovine serum albumin (BSA), various physicochemical and spectroscopic tools such as tensiometry, steady-state fluorescence, synchronous fluorescence, pyrene fluorescence, UV-visible, far-UV circular dichroism (CD) were utilized at physiological pH (7.4) and 298 K in combination with computational molecular modeling analysis. The tensiometric results show significant modifications in interfacial and thermodynamic parameters for m-Py-m GS upon BSA combination, deciphering the gemini surfactant-BSA interaction. Steady-state fluorescence analysis evaluates the structural alterations of BSA with the addition of m-Py-m GS. The plots of Stern-Volmer, modified Stern-Volmer, and thermodynamic parameters were used to determine the binding type of m-Py-m GS to BSA. The synchronous fluorescence spectra state a mild effect of gemini surfactants on the emission intensity of tyrosine (Tyr) residues, on the other hand, tryptophan (Trp) residues showed a significant effect. Post addition of GS, the plot of pyrene fluorescence reveals the mild micropolarity fluctuations via the probe (pyrene) molecules encapsulated in BSA. UV-visible experiments support the complex formation between the BSA and m-Py-m GS. Far-UV CD measurements revealed the modifications in the secondary structure of protein produced by m-Py-m GS. Furthermore, we also used the computational molecular modeling for attaining deep insight into BSA and m-Py-m GS binding and the results are supported with our experimental results.
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Affiliation(s)
- Jeenat Aslam
- Department of Chemistry, College of Science, Yanbu-30799, Taibah University, Al-Madina, Saudi Arabia.
| | - Irfan Hussain Lone
- Department of Chemistry, College of Science, Yanbu-30799, Taibah University, Al-Madina, Saudi Arabia
| | - Farah Ansari
- Department of Chemistry, Faculty of Science, Aligarh Muslim University, Aligarh 202002, India
| | - Afroz Aslam
- Department of Chemistry, Faculty of Science, Aligarh Muslim University, Aligarh 202002, India
| | - Ruby Aslam
- Corrosion Research Laboratory, Department of Applied Chemistry, Faculty of Engineering and Technology, Aligarh Muslim University, Aligarh 202002, India
| | - Mohd Akram
- Department of Chemistry, Faculty of Science, Aligarh Muslim University, Aligarh 202002, India.
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Casimiro L, Maisonneuve S, Retailleau P, Silvi S, Xie J, Métivier R. Photophysical Properties of 4-Dicyanomethylene-2-methyl-6-(p-dimethylamino-styryl)-4H-pyran Revisited: Fluorescence versus Photoisomerization. Chemistry 2020; 26:14341-14350. [PMID: 32652655 DOI: 10.1002/chem.202002828] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Indexed: 11/08/2022]
Abstract
Although 4-dicyanomethylene-2-methyl-6-(p-dimethylamino-styryl)-4H-pyran (DCM) has been known for many decades as a bright and photostable fluorophore, used for a wide variety of applications in chemistry, biology and physics, only little attention has been paid so far to the presence of multiple isomers and conformers, namely s-trans-(E), s-cis-(E), s-trans-(Z), and s-cis-(Z). In particular, light-induced E-Z isomerization plays a great role on the overall photophysical properties of DCM. Herein, we give a full description of a photoswitchable DCM derivative by a combination of structural, theoretical and spectroscopic methods. The main s-trans-(E) isomer is responsible for most of the fluorescence features, whereas the s-cis-(E) conformer only contributes marginally. The non-emitting Z isomers are generated in large conversion yields upon illumination with visible light (e.g., 485 or 514 nm) and converted back to the E forms by UV irradiation (e.g., 365 nm). Such photoswitching is efficient and reversible, with high fatigue resistance. The E→Z and Z→E photoisomerization quantum yields were determined in different solvents and at different irradiation wavelengths. Interestingly, the fluorescence and photoisomerization properties are strongly influenced by the solvent polarity: the fluorescence is predominant at higher polarity, whereas photoisomerization becomes more efficient at lower polarity. Intermediate medium (THF) represents an optimized situation with a good balance between these two features.
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Affiliation(s)
- Lorenzo Casimiro
- ENS Paris-Saclay, CNRS, PPSM, Université Paris-Saclay, 91190, Gif-sur-Yvette, France.,CLAN-Center for Light Activated Nanostructures, Università di Bologna and Consiglio Nazionale delle Ricerche, Via Gobetti 101, 40129, Bologna, Italy.,Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Stéphane Maisonneuve
- ENS Paris-Saclay, CNRS, PPSM, Université Paris-Saclay, 91190, Gif-sur-Yvette, France
| | - Pascal Retailleau
- ICSN, CNRS UPR 2301, Université Paris-Saclay, Gif-Sur-Yvette, 91198, France
| | - Serena Silvi
- CLAN-Center for Light Activated Nanostructures, Università di Bologna and Consiglio Nazionale delle Ricerche, Via Gobetti 101, 40129, Bologna, Italy.,Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Juan Xie
- ENS Paris-Saclay, CNRS, PPSM, Université Paris-Saclay, 91190, Gif-sur-Yvette, France
| | - Rémi Métivier
- ENS Paris-Saclay, CNRS, PPSM, Université Paris-Saclay, 91190, Gif-sur-Yvette, France
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Confinement Effect of Micro- and Mesoporous Materials on the Spectroscopy and Dynamics of a Stilbene Derivative Dye. Int J Mol Sci 2019; 20:ijms20061316. [PMID: 30875908 PMCID: PMC6471191 DOI: 10.3390/ijms20061316] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/08/2019] [Accepted: 03/11/2019] [Indexed: 12/12/2022] Open
Abstract
Micro- and mesoporous silica-based materials are a class of porous supports that can encapsulate different guest molecules. The formation of these hybrid complexes can be associated with significant alteration of the physico-chemical properties of the guests. Here, we report on a photodynamical study of a push–pull molecule, trans-4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM), entrapped within faujasite-type zeolites (HY, NaX, and NaY) and MCM-41 in dichloromethane suspensions. The complex formation gives rise to caged monomers and H- and J-aggregates. Steady-state experiments show that the nanoconfinement provokes net blue shifts of both the absorption and emission spectra, which arise from preferential formation of H-aggregates concomitant with a distortion and/or protonation of the DCM structure. The photodynamics of the hybrid complexes are investigated by nano- to picosecond time-resolved emission experiments. The obtained fluorescence lifetimes are 65–99 ps and 350–400 ps for H- and J-aggregates, respectively, while those of monomers are 2.46–3.87 ns. Evidences for the presence of a charge-transfer (CT) process in trapped DCM molecules (monomers and/or aggregates) are observed. The obtained results are of interest in the interpretation of electron-transfer processes, twisting motions of analogues push–pull systems in confined media and understanding photocatalytic mechanisms using this type of host materials.
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Mohan V, Das N, Das A, Mishra V, Sen P. Spectroscopic Insight on Ethanol-Induced Aggregation of Papain. J Phys Chem B 2019; 123:2280-2290. [PMID: 30775921 DOI: 10.1021/acs.jpcb.8b12063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In this contribution, the structural and dynamic changes occurring to papain in ethanol-water binary solvent mixtures have been investigated and compared with its denatured state. Steady-state fluorescence, solvation dynamics, time-resolved rotational anisotropy, circular dichroism (CD), and single molecular-level fluorescence correlation spectroscopic (FCS) studies were performed for this purpose. In ethanol-water mixtures with XEtOH = 0.6, N-(7-dimethylamino-4-methylcoumarin-3-yl)iodoacetamide (DACIA)-tagged papain was found to undergo a blue shift of 12 nm, while in the presence of 5 M GnHCl, a red shift of 5 nm was observed. Solvation dynamics of the system was also found to be different in the presence of these external agents. In ethanol-water mixtures, the average solvation time was found to increase almost 2-fold as compared to that in water, while in the presence of GnHCl, only a marginal increase could be observed. These changes of DACIA-tagged papain in ethanol-water mixtures are attributed to the aggregation of the protein in the presence of ethanol. The residual anisotropy was found to increase 14-fold, and the rotational time component corresponding to the rotation of the probe molecule was found to increase by 4-fold in the ethanol-water mixture which also gives a notion of the papain aggregation. Atomic force microscopy (AFM) confirms this aggregate formation, which is also quantified by the FCS study. The hydrodynamic radius of the protein aggregates in ethanol-water mixtures was calculated to be ∼155 Å as compared to the corresponding value of 18.4 Å in the case of native monomer papain. Also, it confirmed that the aggregate formation takes place even in the nanomolar concentration of papain. Analysis of circular dichroism spectra of papain showed that an increase in the β-sheet content of papain at the expense of α-helix and the random coil with an increase of the ethanol mole fraction may be responsible for this aggregation process.
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Affiliation(s)
- Vaisakh Mohan
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur 208 016 , Uttar Pradesh , India
| | - Nilimesh Das
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur 208 016 , Uttar Pradesh , India
| | - Aritra Das
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur 208 016 , Uttar Pradesh , India
| | - Vipin Mishra
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur 208 016 , Uttar Pradesh , India
| | - Pratik Sen
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur 208 016 , Uttar Pradesh , India
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Maurya JK, Mir MUH, Maurya N, Dohare N, Ali A, Patel R. A spectroscopic and molecular dynamic approach on the interaction between ionic liquid type gemini surfactant and human serum albumin. J Biomol Struct Dyn 2016; 34:2130-45. [DOI: 10.1080/07391102.2015.1109552] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Jitendra Kumar Maurya
- Biophysical Chemistry Laboratory, Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Muzaffar Ul Hassan Mir
- Biophysical Chemistry Laboratory, Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Neha Maurya
- Biophysical Chemistry Laboratory, Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Neeraj Dohare
- Biophysical Chemistry Laboratory, Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Anwar Ali
- Department of Chemistry, Jamia Millia Islamia (A Central University), New Delhi, India
| | - Rajan Patel
- Biophysical Chemistry Laboratory, Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia (A Central University), New Delhi, India
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Cao C, Huang T, Du FP. Impact of ionic liquid-type imidazolium surfactant additions on dynamic properties of β-casein adsorption layer. Food Hydrocoll 2014. [DOI: 10.1016/j.foodhyd.2013.08.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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De D, Sajjan M, Narayanan J, Bellare JR, Datta A. Nanoconfinement of Water Layers in Lamellar Structures Prepared in the Presence and Absence of Organic Solvent. J Phys Chem B 2013; 117:2106-12. [DOI: 10.1021/jp310371a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dipanwita De
- Department
of Chemistry and ‡Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076,
India
| | - Manas Sajjan
- Department
of Chemistry and ‡Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076,
India
| | - Janaky Narayanan
- Department
of Chemistry and ‡Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076,
India
| | - Jayesh R. Bellare
- Department
of Chemistry and ‡Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076,
India
| | - Anindya Datta
- Department
of Chemistry and ‡Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076,
India
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9
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De D, Santra K, Datta A. Prototropism of [2,2′-Bipyridyl]-3,3′-diol in Albumin–SDS Aggregates. J Phys Chem B 2012; 116:11466-72. [DOI: 10.1021/jp306027h] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Dipanwita De
- Department
of Chemistry, Indian Institute of Technology, Bombay Powai, Mumbai 400 076, India
| | - Kalyan Santra
- Department
of Chemistry, Indian Institute of Technology, Bombay Powai, Mumbai 400 076, India
| | - Anindya Datta
- Department
of Chemistry, Indian Institute of Technology, Bombay Powai, Mumbai 400 076, India
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Wu D, Xu G, Feng Y, Li Y. Aggregation behaviors of gelatin with cationic gemini surfactant at air/water interface. Int J Biol Macromol 2007; 40:345-50. [PMID: 17055045 DOI: 10.1016/j.ijbiomac.2006.09.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2006] [Revised: 09/07/2006] [Accepted: 09/07/2006] [Indexed: 11/23/2022]
Abstract
The dilational rheological properties of gelatin with cationic gemini surfactant 1,2-ethane bis(dimethyl dodecyl ammonium bromide) (C(12)C(2)C(12)) at air/water interface were investigated using oscillating barriers method at low frequency (0.005-0.1 Hz), which was compared with single-chain surfactant dodecyltrimethyl ammonium bromide (DTAB). The results indicate that the maximum dilational modulus and the film stability of gelatin-C(12)C(2)C(12) are higher than those of gelatin-DTAB. At high concentration of C(12)C(2)C(12) or DTAB, the dilational modulus of gelatin-surfactant system becomes close to that corresponding to pure surfactant, suggesting gelatin at interface is replaced by surfactant. This replacement is also observed by surface tension measurement. However, it is found that gelatin-C(12)C(2)C(12) system has two obvious breaks but gelatin-DTAB has not in surface tension isotherms. These phenomena are ascribed to the double charges and strong hydrophobicity of C(12)C(2)C(12). Based on these experimental results, a mechanism of gelatin-surfactant interaction at air/water interface is proposed.
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Affiliation(s)
- Dan Wu
- Key Laboratory of Colloid & Interface Chemistry (Shandong University), Education Ministry, Jinan 250100, PR China
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Sahu K, Mondal SK, Ghosh S, Roy D, Sen P, Bhattacharyya K. Femtosecond Study of Partially Folded States of Cytochrome C by Solvation Dynamics. J Phys Chem B 2005; 110:1056-62. [PMID: 16471642 DOI: 10.1021/jp0538924] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Using femtosecond time-resolved fluorescence spectroscopy, it is shown that the solvation dynamics in the two partially folded states (IS' and IS' ') of a protein, cytochrome C, are very different. In the case of IS' (formed by the addition of 2 mM sodium dodecyl sulfate, SDS) almost the entire dynamic solvent shift of coumarin 153 (C153) is captured in a picosecond setup and the contribution of the ultrafast component (0.5 ps) is very small (5%). Solvation dynamics of IS' ' (formed by 2 mM SDS and 5 M urea) displays a major component (47%) of 1.3 ps. This indicates that the structure of IS' ' is much more open and exposed compared to that of IS'. The difference in the dynamics of IS' and IS' ' is attributed to differences in their structure, particularly near the heme region, and the presence of urea in IS' '.
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Affiliation(s)
- Kalyanasis Sahu
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
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12
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Sen P, Roy D, Mondal SK, Sahu K, Ghosh S, Bhattacharyya K. Fluorescence Anisotropy Decay and Solvation Dynamics in a Nanocavity: Coumarin 153 in Methyl β-Cyclodextrins. J Phys Chem A 2005; 109:9716-22. [PMID: 16833284 DOI: 10.1021/jp051607a] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Fluorescence anisotropy decay and solvation dynamics of coumarin 153 (C153) are studied in dimethyl beta-cyclodextrin (DIMEB) and trimethyl beta-cyclodextrin (TRIMEB) nanocavity in water. C153 binds to DIMEB and TRIMEB to form both 1:1 and 1:2 (C153:cyclodextrin) complexes. The anisotropy decays of C153 in DIMEB and TRIMEB are found to be biexponential. The fast component of anisotropy decay (approximately 1000 ps) is attributed to the 1:1 complex and the slower one (approximately 2500 ps) to the 1:2 complex. From the components of the anisotropy decay, the length of the 1:1 and 1:2 complexes are estimated. Solvation dynamics of C153 in DIMEB exhibits a very fast (2.4 ps) component (41%) and two slower components of 50 ps (29%) and 1450 ps (30%). Solvation dynamics in TRIMEB is described by three slow components of 10.3 ps (24%), 240 ps (45%), and 2450 ps (31%). Possible origins of the ultraslow components are discussed.
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Affiliation(s)
- Pratik Sen
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
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13
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Study of interaction of a cationic protein with a cationic surfactant using solvation dynamics. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.08.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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14
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Roy D, Mondal SK, Sahu K, Ghosh S, Sen P, Bhattacharyya K. Temperature Dependence of Anisotropy Decay and Solvation Dynamics of Coumarin 153 in γ-Cyclodextrin Aggregates. J Phys Chem A 2005; 109:7359-64. [PMID: 16834102 DOI: 10.1021/jp0520143] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Effect of temperature on the fluorescence anisotropy decay and the ultraslow component of solvation dynamics of coumarin 153 (C153) in a gamma-cyclodextrin (gamma-CD) nanocavity are studied using a picosecond set up. The steady-state anisotropy (0.13 +/- 0.01) and residual anisotropy (0.14 +/- 0.01) in fluorescence anisotropy decay in an aqueous solution containing 7 microM C153 and 40 mM gamma-CD are found to be quite large. This indicates formation of large linear nanotube aggregates of gamma-CD linked by C153. It is estimated that >53 gamma-CD units are present in each aggregate. In these aggregates with rise in temperature, the average solvation time (<tau(s)>(obs)) decreases markedly from 680 ps at 278 K to 160 ps at 318 K. The dynamic Stokes shift is found to decrease from 800 cm(-1) at 278 K to 250 cm(-1) at 318 K. The fraction of dynamic Stokes shift (f(d)) detected in a picosecond set up is calculated using the Fee-Maroncelli procedure. The corrected solvation time (<tau(s)>(corr) = f(d)<(tau(s)>(obs)) displays an Arrhenius type temperature dependence. From the temperature variation, the activation energy and entropy of the solvation process are determined to be 12.5 kcal M(-1) and 28 cal M(-1) K(-1), respectively. The ultraslow component and its temperature dependence are ascribed to a dynamic exchange between bound and free water molecules.
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Affiliation(s)
- Durba Roy
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
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15
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Sahu K, Roy D, Mondal SK, Karmakar R, Bhattacharyya K. Study of protein–surfactant interaction using excited state proton transfer. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.01.113] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Prazeres TJV, Fedorov A, Martinho JMG. Dynamics of Oligonucleotides Adsorbed on Thermosensitive Core−Shell Latex Particles. J Phys Chem B 2004. [DOI: 10.1021/jp0489931] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- T. J. V. Prazeres
- Centro de Química-Física Molecular, Instituto Superior Técnico, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - A. Fedorov
- Centro de Química-Física Molecular, Instituto Superior Técnico, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - J. M. G. Martinho
- Centro de Química-Física Molecular, Instituto Superior Técnico, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal
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