title: Application of quantitative 1H NMR for the calibration of protoberberine alkaloid reference standards.
abstract: Quantitative nuclear magnetic resonance spectroscopy (qNMR) has been developed into an important tool in the drug analysis, biomacromolecule detection, and metabolism study. Compared with mass balance method, qNMR method bears some advantages in the calibration of reference standard (RS): it determines the absolute amount of a sample; other chemical compound and its certified reference material (CRM) can be used as internal standard (IS) to obtain the purity of the sample. Protoberberine alkaloids have many biological activities and have been used as reference standards for the control of many herbal drugs. In present study, the qNMR methods were developed for the calibration of berberine hydrochloride, palmatine hydrochloride, tetrahydropalmatine, and phellodendrine hydrochloride with potassium hydrogen phthalate as IS. Method validation was carried out according to the guidelines for the method validation of Chinese Pharmacopoeia. The results of qNMR were compared with those of mass balance method and the differences between the results of two methods were acceptable based on the analysis of estimated measurement uncertainties. Therefore, qNMR is an effective and reliable analysis method for the calibration of RS and can be used as a good complementarity to the mass balance method.
authors: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors: Yan
authors: Y
authors: Wu
authors: National Institutes for Food and Drug Control, Tiantan Xili 2, Beijing 100050, China. Electronic address: heyibj@hotmail.com.
authors: Yi
authors: Y
authors: He
authors: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors: Wenyi
authors: W
authors: He
authors: National Institutes for Food and Drug Control, Tiantan Xili 2, Beijing 100050, China.
authors: Yumei
authors: Y
authors: Zhang
authors: National Institutes for Food and Drug Control, Tiantan Xili 2, Beijing 100050, China.
authors: Jing
authors: J
authors: Lu
authors: National Institutes for Food and Drug Control, Tiantan Xili 2, Beijing 100050, China.
authors: Zhong
authors: Z
authors: Dai
authors: National Institutes for Food and Drug Control, Tiantan Xili 2, Beijing 100050, China.
authors: Shuangcheng
authors: S
authors: Ma
authors: National Institutes for Food and Drug Control, Tiantan Xili 2, Beijing 100050, China.
authors: Ruichao
authors: R
authors: Lin
mesh_terms: D001600:Berberine Alkaloids / Q000032:analysis* / Q000592:standards; D002138:Calibration; D002681:China; D004365:Drugs, Chinese Herbal / Q000032:analysis* / Q000592:standards; D017408:Guidelines as Topic; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D010602:Pharmacopoeias as Topic; D012015:Reference Standards; D015203:Reproducibility of Results
chemical_list: D001600:Berberine Alkaloids; D004365:Drugs, Chinese Herbal; C009090:protoberberine
keywords: Berberine hydrochloride; Palmatine hydrochloride; Phellodendrine hydrochloride; Protoberberine alkaloid; Quantitative NMR; Reference standard; Tetrahydropalmatine