Potentiometric detection of glucose based on oligomerization with a diboronic acid using polycation as an indicator

摘要

A novel potentiometric sensor ford-glucose (Glu) using 4,4 '-biphenyldiboronic acid as a receptor and polyion (poly-N-(3-aminopropyl)methacrylamide, PAPMA) as an indicator is described. The diboronic acid condenses with Gluviaits twocis-diol units to form cyclic or linear oligomeric polyanions which can interact electrostatically with PAPMA, thus efficiently decreasing its potentiometric response on a polycation-sensitive membrane electrode. Althoughd-fructose (Fru),d-galactose (Gal) andd-mannose (Man) show even higher binding affinities to the diboronic acid as compared to Glu, these monosaccharides with only onecis-diol unit cannot oligomerize with the receptor, which efficiently excludes the interferences from the Glu's stereoisomers. The results obtained from blood sample analysis indicate that the proposed sensor is promising for detection of Glu in real-world applications.