title: [Preparation of flavonoid reference standards from Scutellariae Radix under the guidance of high performance liquid chromatography-mass spectrometry analysis].
abstract: Flavonoid reference standards were targeted-prepared from Scutellariae Radix under the guidance of high performance liquid chromatography-mass spectrometry (HPLC-MS) analysis. With HPLC-MS analysis of Scutellariae Radix, 19 flavonoid components were identified by analyzing and comparing their retention times, ultraviolet spectra, and mass spectrometry data with literature. The separation and purification protocols of all targeted flavonoid reference standards were optimally designed according to the results of HPLC-MS analysis and related literature. The ethanol extract of Scutellariae Radix was suspended in water and extracted with petroleum ether, ethyl acetate, and n-butanol successively. The ethyl acetate extract and n-butanol extract were separately subjected to primary separation by low pressure reverse phase preparative chromatography. Then the fractions containing targeted compounds were further purified by low pressure reverse and normal phases preparative chromatography. Finally, baicalin and wogonoside reference standards were obtained from n-butanol extract; baicaelin, wogonin, and oroxylin A reference standards were obtained from ethyl acetate extract. The structures of the 5 reference standards were identified by mass spectrometry (MS) and 1H nuclear magnetic resonance (1H NMR) spectroscopy. The HPLC analytical results showed that the purities of the 5 reference standards were all above 98%. It is demonstrated that the rapid targeted-preparation method under the guidance of the HPLC-MS analysis is applicable for the isolation and preparation of chemical components in traditional Chinese medicines.
authors.affiliation: School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China.
authors.forename: Henan
authors.initials: H
authors.lastname: Guo
authors.forename: Xuedong
authors.initials: X
authors.lastname: Yang
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Wenfeng
authors.initials: W
authors.lastname: Zheng
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D044950:Flavanones / Q000302:isolation & purification / Q000592:standards; D005419:Flavonoids / Q000302:isolation & purification* / Q000592:standards; D013058:Mass Spectrometry / Q000379:methods*; D012015:Reference Standards; D031364:Scutellaria baicalensis / Q000737:chemistry*
chemical_list: D044950:Flavanones; D005419:Flavonoids; C038044:baicalin; C080669:5,7-dihydroxy-6-methoxy-2-phenylchromen-4-one; C085514:wogonin