Regenerable myoglobin biosensor based on protein G immobilized on interdigitated electrodes

Abstract

A simple, sensitive and regenerable biosensor was developed for determining the concentration of myoglobin (Myo). Protein G was employed as an antibody-linking agent, which affords oriented antibody immobilization and the ability to regenerate the sensor. The Myo-antibody of anti-Myo-IgG was immobilized on the protein G layer with its Fc binding domain facing the solution side and thus its orientation allowed easy access for Myo molecules. Electrochemical impedance spectroscopy was used to evaluate the Myo sensor performance. The sensor was able to detect Myo between 10 pg ml−1 and 1 μg ml−1. Regeneration of the sensor was achieved by immersing the electrodes in 0.2 M glycine buffer and by immobilizing fresh antibodies in neutral buffer. The response of the regenerated sensor to Myo was 65% that of the response of the initial sensor.