Extraction and Electrochemical Determination of Curcumin in Curcuma

The content of curcumin in curcuma ranges from 1% to 3%.Curcumin is extracted from curcuma with 95% alcohol.The experiment results show that extraction rate of leaching with ultrasound is the fastest.In 0.2 mol/L phosphate buffer solution(pH 3.3),the voltammetry behaviors of curcumin at a glassy carbon electrode have been studied.One pair of current peaks of the oxidation and deoxidation may be attributed to a reversible one-electron transfer of curcumin molecules at the glassy carbon electrode.For the first time,a new method,the linear sweep stripping voltammetry,for curcumin determination is described in this paper.The beneficiation potential of curcumin is-0.20 V(vs SCE),while its peak potential of curcumin is +0.464 V(vs SCE).The peak current is proportional to the concentration of curcumin over the range of 8.0×10-9 ～4.0×10-7 mol/L.A detection limit of 2.0×10-9 mol/L of curcumin can be estimated under optimized conditions.The method is simple,rapid,sensitive and reliable,so the method can be used directly to detect the content of curcumin in medicine.