Quartz Crystal Microbalance and Atomic Force Microscopy for Study of Carbohydrate-sensitive Multilayers Composed of Pheylboronic Acid Polymers / 分析化学

ABSTRACT

Boronic acids and their derivatives have been widely used in carbohydrate-sensitive materials because they can selectively bind 1,2-and 1,3-diol compounds, including sugars, to form cyclic boronate esters. In this work, pheylboronic acid ( PBA) moieties were grafted onto the backbone of poly( acrylic acid) ( PAA) through the condensation reaction between aminopheyl-boronic acid and carboxylic acid group of PAA in the presence of EDC/NHS, designed as PAA-PBA. Then the resulting PAA-PBA were assembled with poly ( ethyleneimine) ( PEI) to form PAA-PBA multilayer films. The sensing performance of the PEI/PAA-PBA film to carbohydrate (> 50 μg/mL ) , including glucose, fructose, mannose and galactose, has been investigated by combination of the complementary techniques of quartz crystal microbalance ( QCM ) and atomic force microscopy ( AFM) . It was demonstrated that the multilayer showed higher sensitivity to fructose than glucose, mannose and galactose. The interferences of ascorbic acid, uric acid and dopamine to the recognition of glucose can be avoided and the multilayer sensor with excellent long term stability can be recycled by changing pH value of buffer solutions. This system may be potential in realization of high selectivity and high sensitivity sensing system for probing carbohydrate.