A new supramolecular fluorescent probe based on cucurbit[8]uril for visual determination of norfloxacin: Multi-color, quantitative detection, and practical applications

In recent years, the excessive use of antibiotics in agricultural by-products and aquaculture has attracted great attention due to its impact on human health and damage to ecosystems. Therefore, it is of great significance to detect antibiotics with sensitive and intuitive. In this paper, we report a novel fluorescence probe based on multiple chromaticity response for the rapid and sensitive detection of norfloxacin, in which the fluorescence probe was assembled through host–guest coordination between cucurbit[8]uril (Q[8]) and dibromoxanthen-9-one phenylpyridine cationic derivative (DBXPY), named DBXPY@Q[8]. With the addition of norfloxacin, the probe DBXPY@Q[8] provides a continuous fluorescence color change from yellow to blue, and even white fluorescence appears. In the presence of amino acids, pesticides, and other antibiotics, the probe remains unaffected in the detection of norfloxacin with a low detection limit (1.08 × 10−7 M). Interestingly, combined with smart phone RGB analysis, the probe DBXPY@Q[8] enables visual and quantitative detection of norfloxacin without any precision instrument and can be applied to the detection of norfloxacin in food and water. In contrast to traditional NOF detection methods, which are time-consuming, costly, and complex to operate, the use of fluorescent probes allows for the visual analysis and detection of NOF in water and food. It's simple to operate, responsive, and can be monitored in real time, offering a significant improvement over conventional methods and has great application potential in field and quantitative analysis.