Simple PbII fluorescent probe based on PbII‐catalyzed hydrolysis of phosphodiester

Abstract

A new fluorescent probe for Pb^II, p‐nitrophenyl 3H‐phenoxazin‐3‐one‐7‐yl phosphoric acid (NPPA), was designed and synthesized by linking resorufin (serving as a fluorophore and electron acceptor) to p‐nitrophenol (serving as a fluorescence quencher and electron donor) through phosphodiester bonds. When NPPA was irradiated with light, intramolecular fluorescence self‐quenching took place because of the photoinduced electron transfer from the donor to the acceptor. However, upon the addition of Pb^II, the phosphate ester bonds in the probe were cleaved and the fluorophore was released, accompanying the retrievement of fluorescence. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy), 2003