An antifouling electrochemical biosensor based on a protein imprinted hydrogel for human immunoglobulin G recognition in complex biological media

We reported the construction of a specific and long-term antifouling biosensor interface based on a protein imprinted hydrogel for sensitive analysis of human immunoglobulin G (IgG) in complex biological media. The protein imprinted hydrogel was synthesized via a free radical polymerization reaction between a functional monomer of acrylamide and template protein IgG, with the aid of an initiator, a promoter, and a temperature-responsive monomer. The synthesized hydrogel interface effectively reduced nonspecific protein adsorption and undesired cell adhesion, verified by electrochemical tests and fluorescence images. The proposed biosensor quantified the target IgG in a complex biological sample with high sensitivity and selectivity, resulting from good antifouling properties and analytical specificity toward the target. The response range of the reported hydrogel-based biosensor toward IgG was 0.5 - 200.0 ng/mL with a limit of detection of 0.03 ng/mL (S/N = 3). Notably, the developed biosensor could detect the target in a complex biological serum sample.