Nanoenvironmental effect in AOT reverse micelles on the triplet excited state properties of flavins and quenching by molecular oxygen

C.D. BORSARELLI; F.E. MORÁN VIEYRA; L. VALLE

Journal of Physical Organic Chemistry

John Wiley & Sons, Ltd.

Año: 2016 p. 1 - 7

The triplet quantum yield (ΦT) and lifetime (τT) of the lowest excited triplet state of the flavins (3F*), for example, lumiflavin, riboflavin, flavin mononucleotide, and flavin adenine dinucleotide were determined by laser-flash photolysis experiments in Aerosol-OT reverse micelles (AOT RM) dispersed in n-hexane as function of the amount of water dissolved w0 = [H2O]/[AOT]. The energy-transfer quenching of 3F* by triplet molecular oxygen 3O2 to produce singlet molecular oxygen (1O2) was also evaluated by applying a simple pseudophase model for the 3O2 partition between the organic solvent and the AOT RM. The quantum yield of 1O2 generation by the flavins was also calculated. The results are discussed as a function of the nanoenvironmental changes produced in the constrained aqueous interior of the AOT RM as the amount of dispersed water increases.