Boric acid group-functional Tb-MOF as a fluorescent and captured probe for the highly sensitive and selective determination of propyl gallate in edible oils.

[Display omitted] • A boric acid-based Tb-MOF as a fluorescent and captured probe for PG. • The special nucleophilic reaction between the boric acid of Tb-MOF and o-diphenol hydroxyl of PG. • The fluorescence of Tb-MOF significantly quenched with trace amount of PG. • Capable of rapid, sensitive, and selective PG detection. • Successfully determined the presence of PG in soybean oil. This study reports the development of a Tb-metal–organic framework (Tb-MOF)-based fluorescent platform for the detection of propyl gallate (PG). The Tb-MOF using 5-boronoisophthalic acid (5-bop) as the ligand exhibited multiple emissions at 490, 543, 585, and 622 nm under an excitation wavelength of 256 nm. The fluorescence of Tb-MOF was selectively and significantly weakened in the presence of PG due to the special nucleophilic reaction between the boric acid of Tb-MOF and o-diphenol hydroxyl of PG, and the combined effect of static quenching and internal filtering. Furthermore, this sensor enabled the determination of PG within seconds in a wide linear range of 1–150 μg/mL, and with a low detection limit of 0.098 μg/mL, and high specificity against other phenolic antioxidants. This work provided a new route for the sensitive and selective determination of PG in soybean oil, thus was perspective to monitor and reduce the risk of PG overuse. [ABSTRACT FROM AUTHOR]