The electro-catalytic reduction of artemisinin by either hemin or layer-by-layer films of hemoglobin/poly (vinyl sulfonate)

Artemisinin is an important antimalarial drug. The interaction of artemisinin with either hemin or hemoglobin (Hb) may be helpful in understanding the antimalarial mechanism of artemisinin. In the present study, the layer-by-layer films of hemoglobin/poly(vinyl sulfonate) (PVS) were grown on glassy carbon (GC) electrode and silver (Ag) electrode. The atomic force microscopy (AFM), UV-vis and fluorescence spectroscopy were used to characterize the formation of hemoglobin in layer-by-layer films. The (PVS/Hb)(n) films were applied to investigate the interaction of artemisinin and hemoglobin by electrochemical method. The results showed that the hemoglobin in (PVS/Hb)(n) films could catalyze the reduction of artemisinin by lowering the overpotential about 2 10 and 70 mV for GC and Ag electrodes, respectively. The catalytic reduction by the hemoglobin was compared to that by hemin. It suggested that the prosthetic group heme in Hb might induce cleavage of the peroxide bond in artemisinin. (c) 2004 Elsevier B.V. All rights reserved.