Surface Engineering of Phenylboronic Acid-Functionalized Poly(3,4-ethylenedioxythiophene) for Fast Responsive and Sensitive Glucose Monitoring

In this study, we have successfully demonstrated a nanostructured phenylboronic acid-grafted poly(3,4-ethylenedioxythiophene), poly(EDOT-PBA), platform for fast and sensitive glucose monitoring. The poly(EDOT-PBA) films of well-organized tubular nanostructures can be fabricated by direct electropolymerization without templates. Compared to the smooth poly(EDOT-PBA), the nanotubular poly(EDOT-PBA) shows enhanced glucose sensitivity and a different adsorption process of bovine serum albumin (BSA). Besides, the BSA blocking and low concentration of fructose and galactose do not affect the sensitivity of this platform. Both quartz crystal microbalance (QCM) and electrochemical impedance spectroscopy (EIS) methods are used and compared for glucose monitoring by applying nanotubular poly(EDOT-PBA) as conductive substrates. Compared to QCM analysis, EIS has a higher sensitivity to glucose and the detection limit is about 50 mu M. Besides, the binding with glucose on poly(EDOT-PBA) is highly reversibly. On the basis of these observations, the nanotubular poly(EDOT-PBA) has a great potential for enzyme-free electrodes targeting continuous glucose monitoring applications.