Selective Ag + Sensing and Cellular Imaging Based on Hydrophilic Modulated Peptide Probe

ABSTRACT Silver is a highly toxic heavy metal pollutant. Its excessive release into the environment and long‐term accumulation in living organisms can have serious impacts on ecosystems and human health. Therefore, developing precise detection methods for Ag + is crucial for environmental monitoring and biomedical applications. Currently, common peptide fluorescent probes neglect the effects of self‐assembly of probe molecules to form nanoparticles. In this study, we focused on this factor and systematically adjusted the hydrophilicity of peptides to design and synthesize three Ag + responsive fluorescent probes: DNSCI‐SPPW, DNSCI‐APGYHA, and DNSCI‐GPTHC. Among them, DNSCI‐APGYHA exhibits stable morphological characteristics in solution and better selectivity for Ag + . Additionally, this probe shows a lower detection limit (19 nM) and stronger resistance to interference. Notably, DNSCI‐APGYHA demonstrates good cell permeability and low cytotoxicity, and has been successfully applied for fluorescent imaging detection of Ag + in CT26 cells.