胶束电动毛细管色谱法测定板蓝根中苯甲酸、水杨酸和邻氨基苯甲酸

采用胶束电动毛细管色谱法对板蓝根中芳香酸类化合物苯甲酸、水杨酸和邻氨基苯甲酸进行了分离测定。电泳介质(pH 9.8)为20 mmol.L-1硼砂、30 mmol.L-1十二烷基硫酸钠、2 mmol.L-1β-环糊精和4%(体积分数)甲醇组成的混合溶液,以对-羟基苯甲酸为内标,分离电压为16 kV,检测波长为250 nm。在优化的试验条件下,苯甲酸、水杨酸和邻氨基苯甲酸的线性范围分别为40～240 mg.L-1,64～320 mg.L-1和40～400 mg.L-1,检出限(3S/N)依次为0.64,1.08,1.36 mg.L-1。应用此方法分析了板蓝根样品,测定回收率在93.3%～104.2%之间。

Determination of Benzoic Acid,Salicylic Acid and o-Aminobenzoic Acid in Radix Isatidis by Micellar Electrokinetic Capillary Chromatography

Micellar electrokinetic capillary chromatography(MECC) was applied to the separation and determination of aromatic acids,including benzoic acid,salicylic acid and o-aminobenzoic acid,in Radix Isatidis.A mixed buffer solution of pH 9.8 containing 20 mmol·L-1 borate,30 mmol·L-1 SDS,2 mmol·L-1 β-CD and 4%(by vol.) methanol was used as the electrophoretic medium.p-Hydroxybenzoic acid was chosen as internal standard.Separation voltage applied was 16 kV and wavelength of detection was taken at 250 nm.Under the optimum conditions,linearity ranges of benzoic acid,salicylic acid and o-aminobenzoic acid found were between 40-240,64-320 and 40-400 mg·L-1,with detection limits(3S/N) of 0.64,1.08,1.36 mg·L-1 respectively.The proposed method was used in the analysis of sample of Radix Isatidis,giving values of recovery in the range of 93.3%-104.2%.