A biomolecule-based fluorescence chemosensor for sequential detection of Ag+ and H2S in 100% aqueous solution and living cells

The silver ions (Ag+) and hydrogen sulfide (H2S) play extremely an important role in the organism and the environment, while there lack a novel probe with biodegradability, good water solubility, and good bio-compatibility to detect Ag+ and H2S individually. Herein, a novel fluorescence chemosensor DP (Dansyl-Leu-Leu-Cys-Acp-Asp-OH) based on biomolecular peptide has been designed and synthesized, which can be used in the detection of intracellular and environmental Ag+ and H2S. The DP exhibited high selectivity and sensitivity, excellent cell permeation, biodegradability, good water solubility, and pH insensitivity over a biologically relevant range, with detection limits of 61.7 nM and 74.0 nM for Ag+ and H2S, respectively. This work can inspire the design of multi-functional fluorescence sensor based on beacon peptides by modifying lateral and terminal groups for imaging applications in physiological and pathological events.