Analytical Sciences

Abstract − Analytical Sciences, 37(10), 1465 (2021).

Simple Fluorescence Assay for Triethylamine Based on the Palladium Catalytic Dimerization of Benzofuran-2-boronic Acid
Akari TANGE, Azumi HIGASHI, Naoya KISHIKAWA, and Naotaka KURODA
Graduate School of Biomedical Sciences, Course of Pharmaceutical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
Although benzofuran-2-boronic acid hardly emits fluorescence, it can be rapidly converted to a highly fluorescent benzofuran dimer after mixing with a palladium catalyst and amine. We found that a fluorescence enhancement accompanying dimerization was quantitatively promoted upon increasing the concentration of amine. In the present study, we developed a simple fluorescence assay for amines based on the promotive effect. As the result of a fluorescence measurement of the reaction mixture of 19 kinds of typical amines, it was found that tertiary amines including triethylamine (TEA) provided a significant fluorescence enhancement. Finally, the fluorogenic reaction could be applied to develop a high-throughput fluorescent microplate assay for TEA with the limit of detection (blank + 3SD) of 0.091 μM.