Exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins
We report molecular dynamics simulation results of equilibrium and dynamical characteristics pertaining to the solvation of the dye coumarin 153 (C 153) trapped within hydrophobic cavities of di- and trimethylated β-cyclodextrins (CD) in aqueous solutions. We found that stable configurations of the...
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todo:paper_15206106_v112_n30_p8990_Rodriguez2023-10-03T16:20:14Z Exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins Rodriguez, J. Martí, J. Guardia, E. Laria, D. Cyclodextrins Data storage equipment Electric excitation Glucose Hydrophobicity Molecular dynamics Quantum chemistry Solutions Solvation Time domain analysis Aqueous solutions Coumarin 153 Cyclodextrins (CD) Diffusive motions Dynamical characteristics Dynamical response Early stages Electronic excitations Hydrophobic cavities Hydroxyl chains Interconversions Intra-molecular motion Molecular dynamics simulation Picosecond time domain Rotational dynamics Rotational motions Simple modeling Solvation dynamics Solvation response Stokes shifts Subpicosecond Time domain OCT Vertical excitation Dynamics We report molecular dynamics simulation results of equilibrium and dynamical characteristics pertaining to the solvation of the dye coumarin 153 (C 153) trapped within hydrophobic cavities of di- and trimethylated β-cyclodextrins (CD) in aqueous solutions. We found that stable configurations of the encapsulated probe are characterized by a slanted docking, in which the plane of the C153 lies mostly parallel to one of the glucose units of the CD. "In and out" dynamical modes of the encapsulated probe present very small amplitudes. The rotational dynamics of the trapped coumarin can be cast in terms of a simple model that includes diffusive motions within a local restrictive environment coupled to the overall rotational motion of the CD. We have examined the early stages of the solvation response of the environment following a vertical excitation of the probe. Regardless of the degree of CD methylation, the water dynamical response seems to be completed within 2-3 ps and does not differ substantially from that observed for nonencapsulated probes. The CD response is characterized by a single, subpicosecond relaxation that involves intramolecular motions. We also explored dynamical modes that could account for the recently reported persistence of Stokes shifts in the nanosecond time domain. In all cases, the only sources of ultraslow dynamics that we detected were those associated with gauche-trans interconversions in primary hydroxyl chains of the CD, which do not seem to be directly connected to the electronic excitation of the probe. © 2008 American Chemical Society. Fil:Rodriguez, J. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Laria, D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_15206106_v112_n30_p8990_Rodriguez |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Cyclodextrins Data storage equipment Electric excitation Glucose Hydrophobicity Molecular dynamics Quantum chemistry Solutions Solvation Time domain analysis Aqueous solutions Coumarin 153 Cyclodextrins (CD) Diffusive motions Dynamical characteristics Dynamical response Early stages Electronic excitations Hydrophobic cavities Hydroxyl chains Interconversions Intra-molecular motion Molecular dynamics simulation Picosecond time domain Rotational dynamics Rotational motions Simple modeling Solvation dynamics Solvation response Stokes shifts Subpicosecond Time domain OCT Vertical excitation Dynamics |
| spellingShingle |
Cyclodextrins Data storage equipment Electric excitation Glucose Hydrophobicity Molecular dynamics Quantum chemistry Solutions Solvation Time domain analysis Aqueous solutions Coumarin 153 Cyclodextrins (CD) Diffusive motions Dynamical characteristics Dynamical response Early stages Electronic excitations Hydrophobic cavities Hydroxyl chains Interconversions Intra-molecular motion Molecular dynamics simulation Picosecond time domain Rotational dynamics Rotational motions Simple modeling Solvation dynamics Solvation response Stokes shifts Subpicosecond Time domain OCT Vertical excitation Dynamics Rodriguez, J. Martí, J. Guardia, E. Laria, D. Exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins |
| topic_facet |
Cyclodextrins Data storage equipment Electric excitation Glucose Hydrophobicity Molecular dynamics Quantum chemistry Solutions Solvation Time domain analysis Aqueous solutions Coumarin 153 Cyclodextrins (CD) Diffusive motions Dynamical characteristics Dynamical response Early stages Electronic excitations Hydrophobic cavities Hydroxyl chains Interconversions Intra-molecular motion Molecular dynamics simulation Picosecond time domain Rotational dynamics Rotational motions Simple modeling Solvation dynamics Solvation response Stokes shifts Subpicosecond Time domain OCT Vertical excitation Dynamics |
| description |
We report molecular dynamics simulation results of equilibrium and dynamical characteristics pertaining to the solvation of the dye coumarin 153 (C 153) trapped within hydrophobic cavities of di- and trimethylated β-cyclodextrins (CD) in aqueous solutions. We found that stable configurations of the encapsulated probe are characterized by a slanted docking, in which the plane of the C153 lies mostly parallel to one of the glucose units of the CD. "In and out" dynamical modes of the encapsulated probe present very small amplitudes. The rotational dynamics of the trapped coumarin can be cast in terms of a simple model that includes diffusive motions within a local restrictive environment coupled to the overall rotational motion of the CD. We have examined the early stages of the solvation response of the environment following a vertical excitation of the probe. Regardless of the degree of CD methylation, the water dynamical response seems to be completed within 2-3 ps and does not differ substantially from that observed for nonencapsulated probes. The CD response is characterized by a single, subpicosecond relaxation that involves intramolecular motions. We also explored dynamical modes that could account for the recently reported persistence of Stokes shifts in the nanosecond time domain. In all cases, the only sources of ultraslow dynamics that we detected were those associated with gauche-trans interconversions in primary hydroxyl chains of the CD, which do not seem to be directly connected to the electronic excitation of the probe. © 2008 American Chemical Society. |
| format |
JOUR |
| author |
Rodriguez, J. Martí, J. Guardia, E. Laria, D. |
| author_facet |
Rodriguez, J. Martí, J. Guardia, E. Laria, D. |
| author_sort |
Rodriguez, J. |
| title |
Exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins |
| title_short |
Exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins |
| title_full |
Exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins |
| title_fullStr |
Exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins |
| title_full_unstemmed |
Exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins |
| title_sort |
exploring the picosecond time domain of the solvation dynamics of coumarin 153 within β-cyclodextrins |
| url |
http://hdl.handle.net/20.500.12110/paper_15206106_v112_n30_p8990_Rodriguez |
| work_keys_str_mv |
AT rodriguezj exploringthepicosecondtimedomainofthesolvationdynamicsofcoumarin153withinbcyclodextrins AT martij exploringthepicosecondtimedomainofthesolvationdynamicsofcoumarin153withinbcyclodextrins AT guardiae exploringthepicosecondtimedomainofthesolvationdynamicsofcoumarin153withinbcyclodextrins AT lariad exploringthepicosecondtimedomainofthesolvationdynamicsofcoumarin153withinbcyclodextrins |
| _version_ |
1782025323079008256 |