| Popis: |
In this study, we synthesized a new monomer, namely, 3,4-ethylenedioxythiophene bearing a fluoro-containing phenylboronic acid (EDOT–FPBA) for enzyme-free glucose sensing at physiological conditions. The EDOT–FPBA monomer is electropolymerized on a glassy carbon electrode (poly(EDOT–FPBA)/GCE) at a constant voltage. The electrochemical polymerization was optimized to obtain a low impedance film interface and then characterized by scanning electron microscopy, atomic force microscopy, water contact angle measurements, and electrochemical impedance spectroscopy. The specific interaction and pH dependence between poly(EDOT–FPBA)/GCE and glucose are detected by electrochemical impedance spectroscopy in a detection range from 0.05 to 25 mM with a detection limit of 0.05 mM at pH 7.0. The poly(EDOT–FPBA) exhibits 6 times higher sensitivity under physiological pH conditions in comparison with phenylboronic acid and 3-pyridylboronic acid conjugated poly(3,4-ethylenedioxythiophene), due to the introduction of an electron-withdrawing F substituent into the benzene ring of phenylboronic acid (PBA) reducing the pKa value of PBA. The sensitivity and the dynamic range cover all levels of blood glucose in the serum of patients with diabetes. Furthermore, with advantages of high sensitivity and wide detection range, reusability, stability, and mass productivity, poly(EDOT–FPBA) as a glucose sensor has great potential for enzyme-free glucose continuous monitoring applications. |
