Electrochemical sensor for bovine hemoglobin based on a novel graphene-molecular imprinted polymers composite as recognition element

A highly selective and sensitive electrochemical sensor for bovine hemoglobin (BHb) was developed based on a novel graphene-molecular imprinted polymers composite (GR-MIP) as recognition element. The GR-MIP composite was synthesized by oxide self-polymerization of dopamine on the surface of graphene in the presence of template molecules (BHb) in aqueous solution, which is a one-pot facile and green preparation procedure. The fabrication process of the GR-MIP sensor was characterized by differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS), in which [Fe(CN)6]3−/4− was used as an electrochemical active probe. The as-prepared GR-MIP sensor was tested by DPV to investigate the relationship between the current response and BHb concentration. Under optimized experimental conditions, selective detection of BHb in a concentration range of 1.0 × 10−9 mg mL−1 to 1.0 × 10−1 mg mL−1 with detection limit of 2.0 × 10−10 mg mL−1 was obtained, which outperformed the most of reported BHb detecting methods. This novel GR-MIP sensor also exhibited excellent selectivity and good reproducibility, and was used to the determination of BHb in real samples with satisfactory results. The outstanding sensing behavior of the target protein coupled to its low production cost and facile, green preparation procedure makes the GR-MIP sensor attractive in the sensitive and selective detection of target proteins in biological fluids.