Confocal microscopic study on fluorescence quenching dynamics of single latex beads in poly(vinyl alcohol) film

Fluorescence decay curves of single fluorescent polysryrene beads in poly(v inyl alcohol) (PVA) films are measured with a confocal microscope, and quen ching dynamics of the single beans by adsorbed methylene blue (MB) is exami ned. The fluorescence lifetimes oft he beads are identical, while the quenc hing efficiency differs from bead to bend. This is related with inhomogenei ty of adsorbed MB on the beads in PVA films, Nonexponential fluorescence de cays of single beans with MB confirm that fluorophores near the bend surfac e are quenched by adsorbed quencher while the inner part of the bend is not affected. The importance of single bean florescence measurement is discuss ed. Copyright (C) 2000 John Wiley & Sons, Ltd.