Development and application of a cucurbit[6]uril-based supramolecular assembly for specific detection of berberine in water

The extensive use of antibiotics has resulted in the contamination of soil and groundwater, presenting a significant threat to ecosystems. However, the specific detection of antibiotic types in aquatic environments is hindered by high costs and lengthy procedures. Supramolecular fluorescence sensors are regarded as the most promising chemical sensors due to their exceptional stability, high sensitivity, and remarkable fluorescence properties. In this study, cucurbit[6]uril-based supramolecular assembly ((HSA)(CB[6]), (CB[6] = cucurbit[6]uril, HSA = 2-hydroxy-5-sulfobenzoic acid dihydrate) was prepared under solvothermal conditions, utilizing HSA as a structural directing agent. This assembly was employed for the efficient and specific detection of the antibiotic berberine (BER) in water. The experimental results indicate that (HSA)(CB[6]) exhibits excellent acid and alkali resistance as well as recovery performance. Furthermore, the limit of detection for BER in water was determined to be 0.15 μM, with a response time of 7 s. Additionally, (HSA)(CB[6]) was utilized to detect BER in river and lake water, yielding satisfactory recovery rates of 101.8–107.2 % in river water and 95.3–97.2 % in lake water. Moreover, a clear explanation of the mechanism underlying the luminescence quenching of BER for (HSA)(CB[6]) specificity detection is provided.