An oxalamidoquinoline-based fluorescent sensor for selective detection of Zn2+ in solution and living cells and its logic gate behavior

Abstract

A novel fluorescent sensor for Zn2+ based on 8-oxalamidoquinoline (OAQ) was designed and synthesized. OAQ behaves high selectivity to Zn2+ accompanied by remarkable emission enhancement (32 folds) at 490nm upon binding Zn2+ in buffer aqueous solution at pH 7.2. The results show that a 1:1 complex was formed and the apparent association constant of OAQ/Zn2+ complex was calculated to be 2.5×105M−1. The detection limit was gained to be 2.0×10−8M. Furthermore, the fluorescent signals of OAQ are utilized to construct an INHIBIT logic gate at the molecular level. Additionally OAQ was successfully used for fluorescence imaging in living yeast cells.