The pre-binding strategy of phenylboronic acid hydrogel with reducing sugar

Abstract This study systematically explored the influence of pre-binding strategies on the glucose response performance of phenylboronic acid (PBA) hydrogels. To address the issue of a low proportion of active borate anions at physiological pH and limited glucose response due to the high pKa value of PBA (~8-9), the experiment pre-treated PBA polyacrylamide hydrogel with D-galactose, D-fructose and gallic acid, and determined its glucose binding rate (η) by glucose oxidase colorimetric method and optical rotation method. The results showed that the D-fructose pre-binding gel reached equilibrium within 2 minutes, with a significant increase in the binding rate and a shortened equilibrium time. It was speculated that this was related to the reduction of steric hindrance by pre-binding. The pre-binding of D-galactose only increases the binding rate and does not change the equilibrium time. The pre-binding effect of gallic acid is limited, but its medicinal potential deserves attention. Cycling performance tests showed that the pre-binding strategy had a controllable effect on swelling stability (attenuation <10% in the D-fructose/galactose group and <5% after incomplete drying optimization in the gallic acid group), and the upper and lower limits of the binding rate remained stable after 10 cycles of glucose response (the lower limit increase in the D-fructose group decreased from 10% to 5% after optimization with low pH buffer). Research has confirmed that the pre-binding strategy can effectively enhance the physiological environmental glucose responsiveness of PBA hydrogels, providing experimental evidence for the design of smart biomaterials.