The mechanism of fluorescence quenching of the human serum albumin by transferring the energy of the photoinduced electronic excitation from the single tryptophan residue in the structure to the nitrospiropyran donor introduced into its environment is studied by the hybrid computer simulation, including the classical molecular dynamics and the semi-empirical photo-physical calculations for generating the statistical spectra of tryptophan emission and spectra of nitrospiropyran absorption. The probability of the electronic excitation redistribution between the donor and the acceptor is estimated, followed by the photochromic conversion of nitrospiropyran to the merocyanine form, which is readily identifiable due to a significant shift of the longwave absorption band and can be treated as a luminescence detector of the ongoing photoprocesses. The mechanisms of the energy transfer between nonequilibrium fragments in typical combinations of their complex are considered in detail. The general scheme and technical specifics of modeling the optical spectra are illustrated using a simple system of the anthracene molecule in argon. A discussion of several other advanced hybrid approaches of the classical methods in combination with the quantum-mechanical calculations, developed at different theoretical levels and applied in the current computational molecular spectroscopy, is presented.
Предметные области Scopus
- Физика и астрономия (все)