A novel non-enzymatic hydrogen peroxide sensor based on single walled carbon nanotubes–manganese complex modified glassy carbon electrode

A simple procedure was developed to prepare a glassy carbon (GC) electrode modified with single wall carbon nanotubes (SWCNTs) and phenazine derivative of Mn-complex. With immersing the GC/CNTs modified electrode into Mn-complex solution for a short period of time 20–100 s, a stable thin layer of the complex was immobilized onto electrode surface. Modified electrode showed a well defined redox couples at wide pH range (1–12). The surface coverages and heterogeneous electron transfer rate constants ( k s) of immobilized Mn-complex were approximately 1.58 × 10 −10 mole cm −2 and 48.84 s −1. The modified electrode showed excellent electrocatalytic activity toward H 2O 2 reduction. Detection limit, sensitivity, linear concentration range and k cat for H 2O 2 were, 0.2 μM and 692 nA μM −1 cm −2, 1 μM to 1.5 mM and 7.96(±0.2) × 10 3 M −1 s −1, respectively. Compared to other modified electrodes, this electrode has many advantageous such as remarkable catalytic activity, good reproducibility, simple preparation procedure and long term stability.