Performance and Mechanism of Screen-Printed Carbon Paste Electrode Glucose Biosensors Based on Functional Carbon Black

Poly(sodium 4-styrenesulfonate) (PSS) was grafted onto the carbon black surface by ambient, surface-initiated atom radical transfer polymerization. Biologically sensitive film of glucose biosensors was modified with CB-g-PSS by two methods: doping and deposition. The glucose oxidase was immobilized on it by physical adsorption. Thus, two kinds of glucose biosensors were prepared, and different effects were achieved. The experiments indicate that the sensitivity of biosensors doped with CB-g-PSS is one-third that of unmodified biosensors, and the sensitivity of biosensors deposed with CB-g-PSS is 2 times that of unmodified biosensors. Linear range is 1.1 to 33.3 mM. In the various concentration control solutions, the RSD was less than 7%, and the stability was satisfied. The mechanism of modification of biosensors with CB-g-PSS using different methods was analyzed. The results obtained using appropriate methods show that the conductivity and nanometer property of CB-g-PSS benefit immobilization of enzyme, improving kinetic process of enzymatic reaction and increasing the sensitivity of biosensors.