HPLC analysis, semi-preparative HPLC preparation and identification of three impurities in salidroside bulk drug

Salidroside is a bioactive compound mainly distributed in Rhodiola L. (Crassulaceae). It has been widely used in Chinese traditional medicine. In this paper, three impurities were found during the analysis of salidroside bulk drug. The enrichment of impurities was carried out by ODS column chromatography, using methanol-water (13:87, v/v) as eluent and the purification of impurities was achieved by semi-preparative HPLC, using methanol-water (11:89, v/v) as mobile phase, respectively. Three impurities were characterized as 4-(2-hydroxylethyl)-phenol-1-O-β-d-glucopyranoside, 4-hydroxyphenacyl-d-glucopyranoside and p-acetylphenyl-O-β-d-glucopyranoside by a variety of spectral data (IR, UV, MS, 1H NMR, 13C NMR, DEPT and 2D NMR). The simultaneous quantitative determination of salidroside and its impurities (Imp. 1, 2 and 3) was performed by reverse-phase HPLC method with UV detection. Specificity, linearity, sensitivity, precision and accuracy were evaluated.