Selective visualization of endogenous hydrogen sulfide in lysosomes using aggregation induced emission dots

Abstract

The development of novel fluorescent probes for selective detection of endogenous hydrogen sulfide (H₂S) in lysosomes is imperative for elucidating its functions associated with diseases. Nevertheless, the reported fluorescent probes for lysosomal H₂S detection usually undergo an aggregation caused quenching (ACQ) phenomenon in the aggregate state and cause the self-quenching of fluorescence due to the “self-absorption” effect with a small Stokes shift, which largely limited their sensing application. To solve this problem, we present the aggregation induced emission dots (AIED) for selective visualization of endogenous H₂S in lysosomes via a simple co-precipitation method. It is worth noting that AIED with excellent AIE properties and large Stokes shift (∼150 nm) could effectively prevent the notorious ACQ phenomenon and the self-quenching of fluorescence. In addition, the as-prepared AIED exhibits favorable features including good water dispersibility, high sensitivity (∼43.8 nM), outstanding selectivity toward H₂S over other thiols, long-term stability (>15 weeks) and good biocompatibility. Significantly, the resultant AIED with good membrane permeability has been successfully employed to visualize the endogenous H₂S in lysosomes in living cells. We expect that AIED can serve as a useful tool to investigate the roles of lysosomal H₂S in H₂S-associated diseases.