Acyclic cucurbit[n]uril-based sensor array for identification and discrimination of antimicrobial agents

The overuse of antimicrobial has led to the development of antimicrobial resistance, posing a significant health threat. Antimicrobial residues often consist of complex mixtures of structurally similar compounds. The widespread and persistent contaminants make them challenging to detect with conventional techniques. We developed a sensor array based on two acyclic phosphonate hosts and three fluorescent indicators. By using a combination of host-guest complexation and competitive displacement, the array could generate a unique fluorescence response pattern for discrimination of all 10 antimicrobial agents with 100% accuracy. In addition, the array was able to quantitatively determine the concentration of these agents with detection limits below regulatory levels. Its robustness was further validated by successfully analyzing binary mixtures of antimicrobials in real water samples. Although a simplified array maintained accurate identification of all 10 agents, the full array demonstrated superior sensitivity due to the contribution of each sensor unit. This work showed the significant potential of sensor array for identifying and discriminating antimicrobial mixtures with similar structures. The sensor array offers a rapid, sensitive, affordable, and portable approach for environmental monitoring in the real world.