Acyclic Cucurbit[n]uril-Enabled Detection of Aflatoxin B1 via Host-Guest Chemistry and Bioluminescent Immunoassay.

Abstract

Aflatoxin B1 (AFB1), a highly toxic secondary metabolite produced by Aspergillus species, represents a significant health hazard due to its widespread contamination of agricultural products. The urgent need for sensitive and sustainable detection methods has driven the development of diverse analytical approaches, most of which heavily rely on organic solvents, posing environmental challenges for routine food safety analysis. Here, we introduce a supramolecular platform leveraging acyclic cucurbit[n]uril (acCB) as a host molecule for environmentally sustainable AFB1 detection. Screening various acCB derivatives identified acCB6 as a superior host capable of forming a stable 1:1 complex with AFB1 in an aqueous solution, exhibiting a high binding affinity. Proton nuclear magnetic resonance (1H NMR) spectroscopy confirmed that AFB1 was deeply encapsulated within the host cavity, with isothermal titration calorimetry (ITC) experiments and molecular dynamics simulations further substantiating the stability of the interaction, driven by enthalpic and entropic contributions. This supramolecular host was incorporated into a scaffold-assembly-based bioluminescent enzyme immunoassay (SA-BLEIA), providing a green detection platform that rivals the performance of traditional organic solvent-based assays. Our findings highlight the potential of supramolecular chemistry as a foundation for eco-friendly mycotoxin detection and offer valuable insights into designing environmentally sustainable analytical methods.