Construction and Application of Copper Ion and Amino Acid Probe Based on Functionalized Metal–Organic Framework Probe

The rapid development of fluorescence probe technology has promoted in-depth research in fields such as environment and life medicine. Traditional single channel fluorescent probes can achieve highly sensitive detection of targets, but they appear powerless in complex environments. In addition, in today’s deteriorating resource environment, implementing multi target detection with one probe can effectively save preparation resources, which is in line with the development direction of fluorescent probes. To achieve this goal, designing and preparing multi-site probes is undoubtedly the first choice, but the complexity of their preparation is daunting. Herein, we propose the concept of cascade detection for the first time. After the probe completes the first target detection, the complex between the probe and the first target is achieved based on the characteristics of the first target to achieve subsequent target detection. Based on this, a metal–organic framework was used as a basic skeleton and the concept of serial reactions was applied. First, copper ions were detected through coordination. Then, the specificity of copper for sulfur-containing amino acids was utilized to detect the three types of amino acids, and the practical applications of the three probes were studied separately.