Determination of Barbalion in Aloe by Capillary Electrophoresis Coupled with Amperometric Detection

Barbalion in Aloe was determined by capillary electrophoresis coupled with amperometric detection(CE-AD).The pH,type and concentration of the running buffer,the detection potential,the applied voltage and the sampling time were selected as the investigated variables.Under the optimized conditions: a running buffer composed of 30 mmol/L Na2B4O7 buffer at pH 9.5,separation voltage at 15 kV,injection time 10 seconds,2.5% methanol additive and detection potential-0.8 V,a linearity existed between peak area(Y) and mass concentration of Barbalion(c) in a range of 0.05～50 mg/L,r=0.999 4,and the determination limit was 0.01 mg/L.