Synthesis of Fluorescent Functionalized Polyacrylamide and Detection of Cu²⁺ and CN^– in a Pure Water System

In this paper, a fluorescent functionalized polyacrylamide material (P) was prepared by free radical precipitation polymerization based on a coumarin derivative (COMN) and acrylamide (AM). The chemical structure and composition of P were analyzed by ¹H NMR, UV–vis, and FT-IR spectra. The results of fluorescence spectra of common cations illustrate that P can realize the sensitive detection of copper (Cu²⁺) within 30 s in the pure water system, and the fluorescence quenching rate is as high as 95.47%, the limit of detection is 7.2 nM. It is worth noting that the above system rapidly changed from green to orange within 0.5 s. In addition, the fluorescence spectra of common anions reveal that P/Cu²⁺ had a strong interaction with cyanide (CN^–) (0–180 μM), and the limit of detection was 39.12 nM. The results of the cell imaging test show that P still manifests a good fluorescence response to Cu²⁺ and CN^– in HeLa cells, which provides a new method for the detection of these ions in vivo.