A squaraine-based near IR fluorescent chemosensor for calcium.

Abstract

A red to NIR emitting, highly Ca2+-specific fluorescent chemosensor has been synthesized. In pH 7.2 aqueous buffers, the chemosensor signals Ca2+ by a decrease in emission intensity, whereas large excess of Mg2+ ions have no effect on either the absorption or the emission spectrum. The chemosensor is likely to be the prototype of a new generation of laser-diode excitable fluorescent chemosensors for Calcium. (C) 1997 Elsevier Science Ltd.