Separation and determination of curcuminoids in turmeric samples by miceller electrokinetic chromatography with a high molecular mass surfactant

A method of miceller electrokinetic chromatography (MEKC) has been develope d for the analysis of curcuminoids (curcumin, demethoxycurcumin and bisdeme thoxycurcumin) in several turmeric samples. The shattered dry turmeric samp le (0.1g) was extracted with 10 ml of acetone, methanol or ethanol. Ethanol was the best solvent for the extraction of curcuminoids in turmeric sample s. Curcuminoids were successfully separated by high-performance liquid chro matography (HPLC) with linear-gradient elution from 40% to 95% of acetonitr ile containing 0.05% trifluoroacetic add in 15 min, and by MEKC with butyl acrylate-butyl methacrylate-methacrlic acid copolymer sodium salt solution containing 50% dimethyl sulfoxide. Standard curves obtained for curcumin, d emethoxycurcumin and bisdemethoxycurcumin from 6.25 to 100 mug/ml showed st raight lines (r=0.999), the detection limits for curcuminoids by HPLC and M EKC being 0.02 mug/ml (HPLC) and 0.1 mug/ml (MEKC), respectively. Curcumino ids in several turmeric samples from different sources were determined by H PLC and MEKC methods. Compared to the HPLC method, the MEKC method is advan tageous due to its low organic wastes and shorter analysis time. The MEKC m ethod can be applied to quality control analysis of curcuminoids.