Zwitterionic poly(carboxybetaine) hydrogels for glucose biosensors in complex media

Zwitterionic hydrogels based on poly(carboxybetaine) methacrylate (polyCBMA) were developed to protect implantable electrochemical glucose biosensors from biofouling in complex media. To enhance the linearity and sensitivity of the sensing profile, both physical and chemical adsorption methods were developed. Results show that glucose sensors coated with polyCBMA hydrogels via the chemical method achieve very high sensitivity and good linearity in response to glucose in PBS, 10%, 50%, and 100% human blood serum. Essentially identical glucose signals were observed even after prolonged exposure to blood samples for over 12 days. The excellent performance of polyCBMA hydrogel coating offers great promise for designing biocompatible implantable glucose biosensors in biological medium.