One-step electrochemical deposition of antifouling polymers with pyrogallol for biosensing applications

Electrochemical techniques are highly sensitive and label-free sensing methods for the detection of various biomarkers, toxins, or pathogens. An ideal sensing element should be electroconductive, nonfouling, and readily available for conjugation of ligands. In this work, we have developed a facile, one-step electrodeposition method based on pyrogallol polymerization for preparation of a nonfouling and biotinylated surface on indium tin oxide (ITO). A copolymer of sulfobetaine methacrylate and aminoethyl methacrylate (pSBAE) was synthesized and deposited on ITO in the presence of pyrogallol via cyclic voltammetry. The deposition took less than 15 minutes to sufficiently inhibit cell adhesion. Using biotinylated pSBAE, the modified surface resisted nonspecific protein adsorption from the fetal bovine serum solution and detected added avidin concentrations. The results show an efficient platform to fabricate an electrochemical biosensor for the detection of biomarkers. We expect that this facile one-step technology could be applied to conjugate various biosensing elements for nonfouling biosensors.