Rational design of a highly sensitive and selective "turn-on" fluorescent sensor for PO4(3-) detection.

An efficient turn-on fluorescent sensor for PO4(3-) has been developed by rationally designing an in situ-generated iron(iii) complex with a 1,8-naphthalene-based Schiff base unit. The sensor exhibits high sensitivity and selectivity in both solution and solid-state film, even in the presence of other phosphate anions such as HPO4(2-) and H2PO4(-).