Enzyme Assay by Fluorescence Quenching Release: A Novel Fluorometric Method

Abstract

When concentrated fluorescent dye is encapsulated in lecithin liposomes, the fluorescence is Largely self-quenched, The quenching is relieved when the liposomes are disrupted end the escapes. The fluorescence quenching release (FQR) is shown to be proportional to the amount of phospholipase C of C. welchii which hydrolyses lecithin. The FQR method is more sensitive, rapid, and convenient than conventional titrimetric assay and is amenable to automation and Kinetic studies. As a general method, FQR could be adapted to the measurement of other enzymes or agents which disrupt dye-containing microstructures.