Biosensor based on the biocatalysis of microperoxidase-11 in nanocomposite material of multiwalled carbon nanotubes/room temperature ionic liquid for amperometric determination of hydrogen peroxide

A novel nanocomposite material of multiwalled carbon nanotubes (MWCNTs) and room temperature ionic liquid (RTIL) N-butylpyridinium hexafluorophosphate (BPPF6) was explored and used to construct a novel microperoxidase-11 (MP-11) biosensor for the determination of hydrogen peroxide (H2O2). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to characterize the performance of the biosensor. Under the optimized experimental conditions, H2O2 could be detected in a linear calibration range of 0.5 to 7.0 × 10−7 mol L−1 with a correlation coefficient of 0.9949 (n = 9) and a detection limit of 3.8 × 10−9 mol L−1 at 3σ. The modified electrodes displayed excellent electrochemical response, high sensitivity, long-term stability, and good bioactivity and selectivity.