Self-cleaned electrochemical protein imprinting biosensor basing on a thermo-responsive memory hydrogel

Herein, the self-cleaned electrochemical protein imprinting biosensor basing on a thermo-responsive memory hydrogel was constructed on a glassy carbon electrode (GCE) with a free radical polymerization method. Combining the advantages of thermo-responsive molecular imprinted polymers and electrochemistry, the resulted biosensor presents a novel self-cleaned ability for bovine serum albumin (BSA) in aqueous media. As a temperature controlled gate, the hydrogel film undergoes the adsorption and desorption of BSA basing on a reversible structure change with the external temperature stimuli. In particular, these processes have been revealed by the response of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) of electroactive [Fe(CN)₆]^3-/4-. The results have been supported by the evidences of scanning electron microscopy (SEM) and contact angles measurements. Under the optimal conditions, a wide detection range from 0.02μmolL^-1 to 10μmolL^-1 with a detection limit of 0.012 μmolL^-1 (S/N = 3) was obtained for BSA. This proposed BSA sensor also possesses high selectivity, excellent stability, acceptable recovery and good reproducibility in its practical applications.