Naphthalimide based chromofluorescent sensor and DNA intercalator: Triggered by Hg2+/HSO4- cleavage reaction

A novel colorimetric and ratiometric fluorescent probe was synthesized and applied for detection of nanomolar concentration of Hg2+ and HSO4- ions without any interference of other metal ions (Li+, Na+, K+, Ca2+, Mg2+, Ba2+, Co2+, Ni2+, Cu2+, Zn2+, Ag+, Pb2+, Cd2+) and anions (F-, Cl-, Br-, I-, AcO-, NO3-, H2PO4-, HP2O7-, CN-, SCN-). Based on Hg2+/HSO4-triggered cleavage reaction, the probe 1 exhibited a high selectivity and sensitivity for Hg2+ between 0.5 nM and 0.7 mu M, and HSO4-ions between 50 nM and 40 mu M. Furthermore, the probe 1 has been successfully used for studies of the binding interactions with calf thymus (Ct)-DNA. Probe 1 as a DNA intercalator showed fluorescence enhancement upon binding with Ct-DNA and exhibited stronger binding constant as compared to amonafide. (C) 2017 Elsevier B.V. All rights reserved.