Molecularly designed β-cyclodextrin-citric acid hydrogel for dispersive solid-phase microextraction of biogenic...

Biogenic amines are low-molecular-weight nitrogenous compounds naturally present in various foods, whose accurate quantification is essential for quality control and safety monitoring. This study presents a novel and sustainable method for the determination of biogenic amines (BAs) in food samples, particularly vinegar, by integrating molecular modeling with experimental optimization. Molecular docking was used to evaluate the interactions between biogenic amines and both native cyclodextrin monomers (α-, β-, and γ-CD) as well as their polymers crosslinked with citric acid. These insights guided the rational selection of β-cyclodextrin crosslinked with citric acid (p-β-CDCA) as a promising green adsorbent for BAs extraction. A dispersive solid-phase microextraction (d-SPME) procedure was then developed and optimized based on multivariate methodology, identifying the optimum extraction conditions as 20 mg of adsorbent, 8 min of desorption time, and a sample solution pH of 8.0. Under these conditions, high enrichment factors of 368-380 were obtained. The method demonstrated excellent analytical performance, including recoveries of 91.6-95.8%, LOQs of 0.45-0.62 ng mL^-1, intermediate precision of 7.3-9.5%, and a linear range from LOQ to 500.0 ng mL^-1. The developed protocol was successfully applied to determine tryptamine, histamine, and putrescine in both homemade and commercial vinegar samples. These results highlight the potential of combining in silico modeling and d-SPME to develop green, cost-effective, and highly sensitive analytical methods for ultra-trace analysis in food quality assessment.