Analysis of parishin, parishin B and parishin C in Gastrodiae rhizoma by micellar electrokinetic capillary chromatography

To evaluate the quality of Gastrodiae Rhizoma, a simple, rapid and accurate micellar electrokinetic capillary chromatographic method was developed for the assay of three marker constituents - parishin, parishin B and parishin C. The electrolyte was a buffer solution containing 100 mM sodium cholate and 20 mM sodium dihydrogenphosphate adjusted to pH 6.5 with 20 mM sodium tetraborate. Methylparaben was used as an internal standard and detected at 222 nm. The effects of buffer pH, electrolyte, temperature and voltage on separation are discussed. Regression equations revealed linear relationships (correlation coefficients: 0.9992-0.9998) between the peak-area rations of each marker to methylparaben. The relative standard deviations of three marker constituents ranged between 1.23-2.84% (intra-day) and 1.72-3.24% (inter-day). (C) 1998 Elsevier Science B.V.