Related Experiment Video
Updated: Jun 21, 2026

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Deuterium isotope effect on femtosecond solvation dynamics in methyl beta-cyclodextrins
Dibyendu Kumar Sasmal1, Shantanu Dey, Dibyendu Kumar Das
1Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India.
Abstract:
Deuterium isotope effect on the solvation dynamics and fluorescence anisotropy decay of coumarin 153 (C153) bound to dimethyl beta-cyclodextrin (DMB) and trimethyl beta-cyclodextrin (TMB) is studied using femtosecond upconversion. In D(2)O, there is a marked increase in the steady state emission quantum yield and fluorescence lifetime of C153 bound to DMB and TMB. This suggests strong coupling between C153 and D(2)O inside the cyclodextrin cavity. In D(2)O, average solvation time of C153 in DMB is about 1.7 times slower compared to that in water. For TMB in D(2)O, solvation is 1.5 times slower. The deuterium isotope effect on solvation dynamics at long time arises mainly from the longer excited state lifetime. The longest components of solvation dynamics are ascribed to self-diffusion of C153 out of the cyclodextrin cavity. The nearly 1.5 times slower anisotropy decay of C153 bound to DMB and TMB in D(2)O (compared to H(2)O) is attributed to higher viscosity of D(2)O.
More Related Videos
08:40Millisecond Hydrogen/Deuterium-Exchange Mass Spectrometry for the Study of Alpha-Synuclein Structural Dynamics Under Physiological Conditions
Published on: June 23, 2022
11:14Mass Spectrometric Approaches to Study Protein Structure and Interactions in Lyophilized Powders
Published on: April 14, 2015
Related Concept Videos
¹H NMR of Labile Protons: Deuterium (²H) Substitution
Chemical Shift: Internal References and Solvent Effects
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
Stability of Substituted Cyclohexanes
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution