Methylene green-mediated sensor highly sensitive to hydrogen peroxide based on entrapment of horseradish peroxidase in composite membrane of regenerated silk fibroin and poly(vinyl alcohol)

Introduction The detection and quantitative determination of hydrogen peroxide play importantrole in several fields including biochemistry and environmental chemistry.A highlysensitive H202 sensor is useful to fabricate sensor for various substances by combiningit with hydrogen peroxide—producing oxidases.‘Although electrochemical detection ofH202 has been made via its oxidation or reduction at a variety of electrode materials,these electrodes are susceptible to the interference from electr…

Methylene green-mediated sensor highly sensitive to hydrogen peroxide based on entrapment of horseradish peroxidase in composite membrane of regenerated silk fibroin and poly(vinyl alcohol)

A novel composite membrane of poly(vinyl alcohol) and regenerated silk fibroin was employed to immobilize horseradish peroxidase (HRP) and IR was used to give a useful insight into the structure of the composite membrane before and after ethanol treatment. A methylene green-mediated sensor sensitive to hydrogen peroxide was fabricated, based on the composite membrane as immobilization matrix for HRP. Cyclic voltammetry and amperometric measurement were for the first time utilized to demonstrate the suitability of methylene green as an electron transfer mediator between immobilized HRP and a glassy carbon electrode in bioelectrocatalytic reduction of hydrogen peroxide. Performance and characteristics of the sensor were evaluated in respect to response time, detection limit, applied potential and concentration of the mediator. The sensor possesses a variety of characteristics including good sensitivity, rapid response time and low detection of limit of 0.1 umol/L.