The Establishment of the Fingerprint of Bangduling Oral Liquid by the High Performance Liquid Chromatography-Diode Array Detector

Bangduling (BDL) oral liquid, which is a new research and development herbal preparation, comprises four traditional Chinese medicines (TCM): Radix Scutellariae, Cortex Phellodendri Chinensis, Folium Isatidis, and Radix et Rhizoma Rhei. A simple, reliable and reproducible method, based on a high performance liquid chromatography-diode array detector (HPLC-DAD) method, for establishing fingerprint of complex herbal medicine BDL oral liquid was described firstly. In order to develop and validate this HPLC-DAD method, Kromasil C18 column (S-5μm, 4.6 mm × 250 mm) was used with gradient mobile phase at the column temperature of 30°C. The mobile phase was consisted of methanol and water containing 0.1% phosphoric acid. UV wavelength was set at 254 nm. Ten batches of BDL preparations were used to establish the HPLC fingerprint. In addition, the contents of baicalin in the preparations were also determined. Validation of the analytic method was evaluated by stability, precision and repeatability test. Calibration curve for baicalin showed good linearity with R2 = 0.9992. The relative standard deviations (RSDs) value of the relative retention time and peak area in the stability, precision and repeatability test, were less than 1% and 5%, respectively. The similarity of 10 batches of BDL oral liquid was more than 0.958, which showed the preparations from different batch productions were consistent. This established determination method could be efficient to the quality control of BDL oral liquid.