The fluorescent detection of biothiols and antimicrobial study based on copper(I) iodide coordination polymer

Abstract

Luminescent copper(I) iodide (CuI)-based coordination polymers (CPs) are well-known for their structural diversity and strong photoluminescence and are considered as promising candidates for optical applications. Here, a fluorescent Cu2I2(2-ap)2(1) (2-ap = 2-aminopyridine) CP was designed, synthesized, and applied to the effective detection of biothiols and antimicrobial study. Based on the strong thiaphilicity of copper (I), the CP 1 was used as a fluorescent probe to detect biothiols, which play important roles in regulating normal physiological processes due to their vital biological functions. Results revealed that the probe was able to achieve selective and sensitive detection of cysteine (Cys), glutathione (GSH), and homocysteine (Hcy) with low detection limits of 1.013 μM, 1.051 μM, and 1.034 μM, respectively. Moreover, the probe was successfully applied to the detection of thiols in human urine, fetal bovine serum, and bovine serum albumin, which demonstrated the potential application in biological samples. Furthermore, a CP/cellulose nanofibers (CP/CNFs) composite film was fabricated for visual detection of biothiols and antimicrobial study. The developed composite film showed good antimicrobial activity against tested bacteria in vitro conditions, thus opening up the antimicrobial application of CP-doped composite film and providing a new perspective and prospect for potential application in food packaging.