A two-photon fluorescent probe for detecting endogenous hypochlorite in living cells

A novel two-photon fluorescent probe (HQ) for hypochlorite (ClO-) has been developed based on specific ClO- -promoted oxidation of a C=N bond. The probe shows linear fluorescence responses to ClO- with 23.5-fold enhancement. Two-photon fluorescence detection signals of HQ to ClO- were observed with high selectivity and sensitivity. The good biocompatibility guaranteed the use of HQ to detect intracellular ClO- under two-photon excitation. Moreover, HQ has been successfully applied to monitor the endogenously produced hypochlorite in living cells (BV-2) stimulated by lipopolysaccharide (LPS). HQ provides a new ClO- detection agent for the discovery of pharmacological microglia modulators by high-throughput screening.