Studies On Quality Control Methods For The Purification Process Of Scutellaria Baicalensis Water Extract

Scutellaria baicalensis (SB) is widely used as an ingredient in a variety of traditional Chinese medicine preparations. The raw material of SB needs to be extracted, purified and dried during manufacturing process, which would lead to the degradation of flavonoid glycosides. Given the status, scutellarin, baicalin and wogonoside were selected as quality attributes herein for the systematic studies on the purification process of Scutellaria baicalensis water extract (SBWE). Relationships between material attributes, process parameters and quality attributes were established for the purpose of improving the transferring rate of effective components. In addition, two rapid analytical methods for the quantification of these components in SBWE were established and compared, which also provided technical support for the quality control of the material in the purification process of SBWE. The main contents and achievements of this thesis are summarized as follows:1. A high performance liquid chromatography (HPLC) method to determine the contents of four components in SBWE was developed. The contents of scutellarin, baicalin, wogonoside and baicalein in SBWE were determined under the same chromatographic condition.2. Critical process parameters for the purification process of SB WE were determined. Fractional factorial design of experiments was conducted to evaluate the significance of seven potential parameters to quality attributes in the purification process of SBWE. Concentration of SBWE, pH of acid precipitation, temperature and pH of alkali dissolution were identified as the critical parameters.3. Further optimization for the purification process of SBWE was conducted by applying Box-Behnken design of experiments. Mathematical models relating attributes of SBWE, process parameters and quality attributes were established. The range of the parameters was obtained and the established models were proved to be reasonable by the verified experiment.4. Rapid quantification methods for four components in SBWE were established based on near-infrared spectroscopy (NIRS) and ultraviolet (UV) spectroscopy respectively. This approach offers an opportunity to achieve rapid analysis of the attributes of material in the purification process of SBWE.