UV/vis Spectroelectrochmistry And CE-UV/vis Determination Of Soybean Isoflavones

Soybean isoflavone(SIF),one of flavonoids compounds,is a natural antioxidant.It has high nutriology value and treatment meaning,can combine with ER,shows estrogen effect,so we also call it plant estrogen.In the near future,many studys discover that SIF plays an important role in preventing and treating of many diseases such as turnout,cardiovascular disease,osteoporosis and menopause syndrome.Genistein(GE)and daidzein(DA)are both belong to SIF,have complex electro-oxidation mechanism,little literatures about their electric oxidation-ruduction process has been reported until now.This work studied in Britton-Robinson buffer solutions involving 0.5 mol·L^-1KC1 as supporting electrolyte,studyed the electrochemistry behaviors of GE and DA on graphite-wax electrode(GWE)respectively with cyclic voltammetry(CV)and differential pulse voltammetry(DPV),used the double potential chronoabsorptometry tested the in situ thin layer spectroelectrochemistry process and the high performance capillary electrophoresis(HPCE)-UV/vis in separate detecting of the tow SIF.The results:first,the two SIF have very similar electrochemistry characteristic, it means that 5-OH of the flavone carbocyclic has no infection nearly to the electric oxidant reactions of SIF,4¹-OH of B-ring occur 1e^-/1H⁺ oxidant reactions are main electric oxidant reactions,and go with succedent chemic translation;second, home-made GWE has strong adsorption to SIF,can strengthen reaction current signal,so it's suit as work electrode,DPV can carry on electrochemistry micro detection,the limits of detection range both are about 4×10^-7mol·L^-1;third,it offers much dynamic information in using the UV/vis spectroelectrochmistry,then with computer can achieve reconstructed results for corresponding composings. These curves correspond to the change of thin layer solution concentration of different composings,eliminate adsorbed components' contribution and charge/ discharge current resulted by step,can reflect speed of some confirmed components which participate in process of liquid phase,and no limit electron transfer process; fourth,we use HPCE separate the tow SIF triumphantly.