Co-binding-based supramolecular sensor array for fluorescence recognition of chitin synthesis inhibitors

The extensive agricultural use of chitin synthesis inhibitors (CSIs) has garnered significant concern due to their environmental persistence and potential ecological risks. A persistent challenge in this context is the concurrent discrimination and quantitative detection of multiple CSI residues in complex matrices. To address this issue, we developed a fluorescent sensor array utilizing a supramolecular system for the identification and quantification of four common CSIs: buprofezin, chlorfluazuron, diflubenzuron, and flufenoxuron. This system exploits the co-binding of a fluorescent indicator and CSI within the hydrophobic cavity of albumin, inducing pattern-based ratiometric fluorescence responses. The generated unique fluorescence fingerprint profiles for each CSI enable differentiation through multivariate statistical analyses, including linear discriminant analysis (LDA) and hierarchical cluster analysis (HCA), yielding 100 % classification accuracy across both individual CSIs and their mixtures. Furthermore, quantitative detection is facilitated by a linear correlation between LDA feature scores and CSI concentrations. The practical utility of this platform was substantiated by successful discrimination of CSIs in real-world samples, including millet, soil, and aqueous environments, with performance maintained across diverse matrix compositions, offering a critical advancement in addressing the analytical challenges posed by these persistent pesticide residues.