Both visual and ratiometric fluorescent sensor for Zn2+ based on spirobenzopyran platform

Abstract A ratiometric fluorescent Zn 2+ chemosensor, SPQH , based on spirobenzopyran platform, was synthesized. In aqueous HEPES 7.4 buffer solution, upon chelation with Zn(II), SPQH demonstrates high selectivity and subnanomolar sensitivity for zinc ion with 36-fold enhancement in the NIR fluorescence output.