Development of high-performance electrochemical enzyme biosensors based on carbon nanotube complexes with conjugated polyelectrolytes
A simple and facile route for the construction of highly sensitive electrochemical enzyme biosensors has been proposed using carbon nanotube (CNT) complexes with a conducting poly(thiophene) polymer. Glucose oxidase was used as a model enzyme for the construction of the advanced biosensors. Glucose biosensors, exhibiting sensitivity higher than any biosensor based on CNTs and other polymers reported, were prepared by depositing CNT-polymer loaded polymer layers that contained entrapped glucose oxidase onto gold electrodes. It has been shown that the CNT-polymer complexes offer an enzyme-friendly versatile platform for the immobilization of enzymes with increased electron-transfer rate, high electrical conductivity, and excellent film quality. The obtained results pave the way for the development of other advanced CNT-based biosensors. Further investigations will involve elimination of interferences and incorporation of other enzymes for highly sensitive detection of H2O2, ethanol, and NADH (a cofactor in many naturally occurring enzymatic reactions) etc.