A corrole-based fluorescent probe for detection of sulfur ion and its application in living cells

A dual signaling probe DPC-O-NBD formed through the conjugation of 5,15-bis(phenyl)-10-(4-hydroxylphenyl)-cormle (DPC-OH) with 4-chlom-7-nitrobe-nzo-2-oxa-1,3-diazole (NBD-Cl) is explored to detect sulfur ion (S2-). The key design principle is based on the nucleophilicity of S2-, which can be used to cleave the bridging ether bond in the probe to obtain both fluomgenic and chromogenic signaling behaviors. Importantly, the probe DPCO-NBD not only showed a high sensitivity (LOD: 48 nM) and selectivity over other interfering species, but also exhibited a rapid response (similar to 18 s) towards S2-. Furthermore, DPC-O-NBD can also be used to detect S2- in both water and live cells, providing a potentially powerful approach for probing S2- chemistry in biological systems.