Dual-mode optical chemodosimeter for detecting copper ions in the environment, food, and living organisms with smartphone

Techniques for the detection and quantification of active ingredients in plants and foods are of global interest in the field of smart agriculture. The amount of copper ions (Cu2+) in the environment is closely related to water quality, food safety, and biological health. However, the drawbacks of the current copper ions detection techniques include difficult operation and inconvenient field analysis. Due to the reliable analytical parameters, dualmode optical analysis has become increasingly interesting and popular. Therefore, in this study, a dual-mode optical copper ions detection method was constructed based on a fluorescent chemodosimeter RH-HP. The reaction-based recognition process improves its specificity for copper ion recognition and can be utilized to determine the concentration of copper ions in water samples, agricultural products, cells, and zebrafish. It is worth noting that the analysis and photo function of the smartphone is used to establish the relationship between the change of color RGB values and copper ions concentration. This work offers an economical, portable tool for the in-situ detection of copper ions, demonstrating its potential application for monitoring plant growth processes in future smart agriculture, and provides a reference for the establishment of in-situ portable detection methods for other important substances.