Guest adaptative supramolecular sensing strategy for warning the risky aflatoxins in contaminated cereals

In the face of diversified analytes, it is a great challenge and infeasible task to design and synthesize corresponding macrocyclic hosts to realize the ideal supramolecular sensing. Herein, we proposed a novel supramolecular sensing strategy, guest adaptative assay (GAA), in which analyte was quantitatively transformed under mild conditions to perfectly adapt to macrocyclic host. As a health-threatening "landmine" in cereals, aflatoxins were converted by the aid of alkali hydrolysis to satisfactorily obtain aflatoxins transformants in ionic state, resulting in sensitive response by the guanidinocalix[5]arene•fluorescein reporter pair. Surprisingly, the established strategy not only exhibited effective practicality in screening out high-risk cereals contaminated with aflatoxins, but also relieved the laborious task of macrocycle design and screening in supramolecular sensing. Aflatoxins are toxic metabolites of Aspergillus flavus and A. parasiticus that easily contaminates agricultural crops, leading to millions of cases of aflatoxins-induced diseases, which pose a great threat to human health, environment, and economy worldwide. In this work, a new supramolecular sensing strategy, guest adaptative assay (GAA), was successfully employed to quickly capture high-risk cereals (peanut, corn, semen coicis, and malt) contaminated with AFBs and release the safety cereals. The work reported herein not only presents an interesting avenue for the rapid warning of the high-risk cereals contaminated AFBs, but also broadens the application scenarios of supramolecular sensing.