title: [Determination of gambogic acid in Gamboge by non-aqueous capillary electrophoresis].
abstract: Gambogic acid (GA), a kind of caged xanthones, has low solubility in water. A non-aqueous capillary electrophoresis (NACE) was established for the determination of GA in Gamboge based on the optimized conditions. The effect of 20% - 60% methanol or acetonitrile spiked in running solution was investigated. The effects of compositions, concentration, pH, additives like β-cyclodextrin in running buffer were thoroughly studied. Applied voltage and applied temperature were also observed. Optimal electrophoretic conditions were as follows: 20 mmol/L sodium borohydride solution (pH 9. 86) containing 40% (v/v) acetonitrile, 10 mmol/L β-cyclodextrin as running buffer, applied voltage of 10 kV, capillary temperature of 30 °C and detection wavelength of 280 nm. The calibration curve had good linearity in the range of 2-2 000 mg/L with the correlation coefficient of 0. 999 6. The limit of quantification (S/N= 3) of the method was 2 mg/L. The quantifications of GA in Gamboge from different producing places including Vietnam, Thailand, Burma, India were 1. 67-472.40 mg/g with the RSD (n= 3) of 1.12% -2.60%. The content of Gamboge from Vietnam is obviously low while the others are high. The recoveries of GA spiked in real samples ranged from 95. 2% to 105. 6%. The method of NACE is simple, efficient and of good reproducibility, can be served as a novel reference to identify and control the quality of Gamboge.
authors.forename: Wanlu
authors.initials: W
authors.lastname: Ou
authors.forename: Yujuan
authors.initials: Y
authors.lastname: Li
authors.forename: Dongdong
authors.initials: D
authors.lastname: Shi
authors.forename: Feng
authors.initials: F
authors.lastname: Qu
mesh_terms: D019075:Electrophoresis, Capillary; D029760:Garcinia / Q000737:chemistry*; D011786:Quality Control; D044004:Xanthones / Q000032:analysis*
chemical_list: D044004:Xanthones; C052659:gambogic acid