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 20-100s, 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 X 10(-10) mole cm(-2) and 48.84 s(-1). The modified electrode showed excellent electrocatalytic activity toward H2O2 reduction. Detection limit, sensitivity, linear concentration range and k(cat) for H2O2 were, 0.2 mu M and 692 nA mu M-1 cm(-2). 1 mu M to 1.5 mM and 7.96(+/- 0.2) X 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. (C) 2010 Elsevier Ltd. All rights reserved.