An electrode was developed for the determination of hydrogen peroxide (H(2)O(2)). It contains a chitosan-copper complex onto which multi-wall carbon nanotubes in an ionic liquid were deposited. The modified electrode exhibited excellent electrocatalytic activity that was applied to the detection of H(2)O(2). The pH value and the effect of electrical potential on the current response were optimized. The electrode displays good stability, an expanded linear response range, improved electrocatalytic activity towards H(2)O(2), and enables detection of H(2)O(2) with a linear response from 0.02 to 13 mM of H(2)O(2), with a correlation coefficient of 0.997 and a response time of <6 s. The detection limit is 1.0 mu M (at S/N = 3). Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.