Design and application of Cd polypeptide fluorescent probes based on Aggregation Induced Emission (AIE).

Cadmium is a toxic heavy metal, which is both an environmental pollutant, and a threat to human health. A fluorescent probe was developed to detect Cd selectively, sensitively, and quickly. This study reports the successful development of a polypeptide fluorescent probe TPE-HC (TPE-His-Pro-Gly-Cys) which selectively detects Cd by Aggregation-Induced Emission effect. After fluorescence excitation, Cd can be effectively detected based on the change of fluorescence intensity. The detection limit of Cd in buffer solution was determined to be 151 nM (R = 0.9933). This probe exhibits high sensitivity, high cell permeabilit y, and low biological toxicity, and can perform live cell imaging under biological conditions. This study indicates that TPE-HC can detect Cd in biological environments.