cis-Diol functionalization via three-component reaction for boronate affinity separation and in situ fluorescence...

Boronic acid-functionalized materials show great promise for the selective capture of cis-diol-containing compounds; however, their application to analytes lacking such structural motifs, such as biogenic amines (BAs), remains a significant challenge. Primary BAs are transformed into cis-diol-functionalized isoindoline derivatives via a three-component reaction involving o-phthalaldehyde (OPA) and 3-mercapto-1,2-propanediol (MPD). This derivatization enables selective solid-phase microextraction through boronate affinity interactions and fluorescence analysis. This method exhibits excellent linear response (R² = 0.9959) over the range of 1-100 μmol/L, a low limit of detection (LOD = 0.2873 μmol/L), and good intra-day precision (RSD ≤ 2.18%). The developed method was applied to determine total BAs as cadaverine equivalents in fish, kumiss (fermented mare's milk) and cheese. This study employed chemical derivatization to construct dual-functional derivatives capable of both fluorescence detection and boronate affinity interactions, enabling in situ analysis on the fiber surface and thereby expanding the application of boronic acid-functionalized materials.