Ratiometric probe AMC@ZIF-8 integrating intelligent algorithm and HSV mode for visual on-site detection of tetracycline in environmental water samples

Abstract

The residues of tetracycline (TC) in the environment pose a serious threat to ecosystems and human health, and it is difficult to meet the on-site rapid monitoring requirements. Therefore, the development of an intelligent, portable, visualized detection device for TC is of great significance for achieving real-time environmental monitoring and accessible food safety control. Herein, a non-fluorescent metal-organic framework material (ZIF-8) was combined with blue-emitting 7-amino-4-methylcoumarin (AMC) via electrostatic interaction to construct a high-efficiency ratiometric probe AMC@ZIF-8 for the detection of TC. The blue fluorescence of AMC, which did not react with TC, serving as the reference signal at 452 nm, while the aggregation-induced emission (AIE) effect between TC and ZIF-8 produced a yellow-green fluorescence at 525 nm, using as the response signal. Therefore, a linear relationship between the AMC@ZIF-8 composite and the added TC was obtained over the range of 0.03–40 μM. This ratiometric fluorescent probe demonstrated recovery rates of 95.4 %–107.8 % (RSD ≤ 4 %) in real water samples, with a detection limit as low as 10.08 nM. Furthermore, an intelligent application based on the random forest algorithm was developed, which could extract hue, saturation, and value features from the HSV color space. The model achieved a test set accuracy of 99.41 % within the 0–50 μM concentration range. The application integrates image acquisition, feature extraction, and visual concentration prediction functions, and supports real-time analysis on smartphones, offering a low-cost, high-accuracy semi-quantitative solution for food safety and environmental monitoring.