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

Area of Science:

• Environmental Science
• Analytical Chemistry
• Biomedical Engineering

Background:

• Silver (Ag+) is a toxic heavy metal pollutant with significant environmental and health impacts.
• Accurate detection of Ag+ is vital for environmental monitoring and biomedical applications.
• Existing peptide fluorescent probes often overlook the self-assembly of probe molecules into nanoparticles.

Purpose of the Study:

• To design and synthesize novel Ag+-responsive fluorescent probes by adjusting peptide hydrophilicity.
• To investigate the impact of self-assembly on probe performance.
• To identify a highly selective and sensitive probe for Ag+ detection.

Main Methods:

• Systematic adjustment of peptide hydrophilicity to synthesize three fluorescent probes: DNSCI-SPPW, DNSCI-APGYHA, and DNSCI-GPTHC.
• Evaluation of probe selectivity, detection limit, and interference resistance.
• Assessment of cell permeability and cytotoxicity for in-cell imaging applications.

Main Results:

• DNSCI-APGYHA demonstrated stable morphology, superior selectivity for Ag+, and a low detection limit of 19 nM.
• This probe exhibited enhanced resistance to interference compared to others.
• DNSCI-APGYHA showed good cell permeability and low cytotoxicity, enabling successful Ag+ imaging in CT26 cells.

Conclusions:

• The study highlights the importance of considering molecular self-assembly in designing peptide fluorescent probes.
• DNSCI-APGYHA is a promising tool for sensitive and selective detection of Ag+ in complex biological and environmental samples.
• The developed probe facilitates advanced applications in cellular imaging and environmental monitoring of silver contamination.