Determination of quinolizidine alkaloids in Sophora tonkinensis by HPCE.
A simple, rapid and reliable high-performance capillary electrophoresis method has been developed to determine quantitatively the alkaloid content of Sophora tonkinensis, a Chinese herb commonly known as shan-dou-gen. A total of seven quinolizidine alkaloids (cytisine, sophocarpine, matrine, lehmannine, sophoranol, oxymatrine and oxysophocarpine) could be readily separated within 15 min. The running buffer was 50 mM phosphate buffer (pH 2.5) containing 1% hydroxypropyl-beta-cyclodextrin and 3.3% isopropanol in water. The applied voltage was 25 kV, the capillary temperature was 25 degrees C, the detection wavelength was 200 nm and scopolamine butylbromide was used as internal standard. The method was used to analyse the chemical constituents of two commercial alternatives to shan-dou-gen. The alkaloid constituents of authentic shan-dou-gen gave a specific HPCE electropherogram that could be used to distinguish the drug from potential substitutes. Furthermore, the content of oxymatrine and the total content of the seven quinolizidine alkaloids could be used as quantitative markers in order to assess the quality of S. tonkinensis.
Ding
Pei-lan
PL
Department of Pharmacognosy, School of Pharmacy, Fudan University, 138 Yixueyuan Road, Shanghai 200032, People's Republic of China.
Yu
Yun-qiu
YQ
Chen
Dao-feng
DF
D000470:Alkaloids / Q000302:isolation & purification*; D002681:China; D016000:Cluster Analysis; D004365:Drugs, Chinese Herbal / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000379:methods; D018517:Plant Roots / Q000737:chemistry; D011807:Quinolizines / Q000302:isolation & purification*; D015203:Reproducibility of Results; D027343:Rhizome / Q000737:chemistry; D029909:Sophora / Q000737:chemistry*
D000470:Alkaloids; D004365:Drugs, Chinese Herbal; D011807:Quinolizines