Electrochemistry and voltammetric determination of colchicine using an acetylene black-dihexadecyl hydrogen phosphate composite film modified glassy carbon electrode

The electrochemical behavior of colchicine at an acetylene black-dihexadecyl hydrogen phosphate (denoted as AB-DHP) composite film coated glassy carbon electrode (GCE) was investigated using cyclic voltammetry (CV), linear sweep voltammetry (LSV) and differential pulse voltarnmetry (DPV). Compared with the poor electrochemical signal at the unmodified GCE, the electrochemical response of colchicine at the AB-DHP film modified GCE was greatly improved, as confirmed from the significant peak current enhancement. The remarkable peak current enhancement indicates that the AB-DHP modified GCE has great potential in the sensitive determination of colchicine. Thus, all the experimental conditions, which influence the electrochemical response of colchicine, were studied and the optimum conditions were achieved. Finally, a sensitive and simple voltammetric method with a good linear relationship in the range of 1.0 X 10- 7 -4.0 x 10-5 mol/L, was developed for the determination of colchicine. The detection limit of colchicine was also examined and a low value of 4.0 x 10-8 mol/L for 4-min accumulation was obtained (SIN= 3). This electrode was successfully applied to detect colchicine in human urine samples. (c) 2005 Elsevier B.V. all rights reserved.