Investigations on Bioanalytical Chemistry Part I. On Differential Pulse Voltammetry of Bilirubin

The electrochemical behaviour of the bilirubin in many kinds of supporting electrolytes on a glassy carbon electrode (GCE) and a hanging mercury drop electrode (HMDE) was investigated by means of anodic or cathodic differential pulse voltammetry. The influences of different methods of pre-treatment of the glassy carbon electrode was also discussed. In Na2B4.O7-KH2PO4 buffer solution, the linear range was 2×10−9-1×10−9 mol/l and the detection limit was 3.3×10−9 mol/l by anodic differential pulse voltammetry at GCE. A linear relationship holds between the peak current and the concentration of bilirubin in a concentration range of 1×10−9-4×10−7 mol/l with good precision and accuracy, and the limit of detection was 2×10−10 mol/l, when cathodic differential pulse adsorption voltammetry at HMDE was used.