Flavonoids On Xanthine Oxidase And Electrochemical Studies Of Human Breast Cancer Cells

Two aspects were studied in this paper: 1. Investigated the inhibition mechanism of flavanoid to XOD and direct electrochemical character of XOD by the electrochemistry method. 2. Investigated the inhibition mechanism of flavanoid to MCF-7 by the electrochemistry method. Cyclic voltammetry, UV-vis, HPLC, MTT and transmission electron microscope were used in this researches. The results as shown:(1) Prepared the XOD/SWNT+DDAB/EPG modified electrode, and the direct electronic transmission of XOD was implemented on this modified electrode. The peak potentials were found to be pH dependent with a slop of 70mV/pH. The peak currents were found to be sweep rate dependent, so the oxidation-reduction reaction was two electrons transfer accompany the same proton transportation, and the oxidation-reduction process of XOD on the electrode was controlled by surface. There were catalysis and sensitive of xanthine on the eletrode. Apigenin and Quercetin had rejection capability to XOD, the IC50 of Apigenin and Quercetin were 5×10-6 mol/L and 1.5×10-5 mol/L, but Rutin had no rejection capability to XOD nearly, and the order was: Apigenin﹥Quercetin﹥Rutin. The inhibition capability to XOD had depended on concentration and time, which were consistent with the UV-vis.(2) Investigated the electrochemical character of the MCF-7 cell, and contrasted the electrochemical character of the integrity cell, eluent and cytoplasm. Found that the voltammetric response of the MCF-7 cell was produced mostly from the extracellular speciese: xanthine and guanine which secreted by. We adopted ultrasonic to shatter the MCF-7 cell to evaluate the activation of it and scout the growth status of it, so we could get the more sensitive voltammetric response. We investigated the inhibition mechanism of flavanoid to MCF-7 by the electrochemistry method. Luteolin, Qquercetin, Quercetin-3-β-D-glucoside and Rutin had rejection capability to MCF-7 cell, the IC50 of Luteolin, Qquercetin and Quercetin-3-β-D-glucoside were 9.77, 32.8, 64.7 and 98.7μg/mL, and the order was: Luteolin﹥Qquercetin﹥Quercetin-3-β-D-glucoside﹥Rutin. The inhibition capability to MCF-7 cell had depended on concentration and time, which were consistent with the MTT.