摘要
采用毛细管电泳电化学检测法测定了胡黄连中香草酸和阿魏酸的含量 ;研究了电极电位、运行缓冲液的浓度和酸度、电泳电压及进样时间等对电泳的影响 ,得到了最优化的测定条件 ;以直径为300μm的碳圆盘电极为检测电极 ,工作电极电位为0.8V(vs.SCE) ,在50mmol/L硼砂(pH8.4)运行缓冲液中 ,上述两组分在8min内完全分离 ;香草酸和阿魏酸线性范围分别为5×10-4～1×10-6 mol/L和1×10-3～1×10-6 mol/L ,检出限分别为4.2×10 -7和3.0×10 -7mol/L ;7次平行进样的相对标准偏差(RSD)为2.2 %和2.8 % ,回收率(n=3)分别为99%和103 % ,该法灵敏可靠 ,结果令人满意。
The determination of vanillic acid and ferulic acid in Rhizoma Picrorhizae by capillary electrophoresis with electrochemical detection(CE-ED)was reported in this paper.The effects of working electrode potential,concentration and pH value of the running buffer,separation voltage and injection time were investigated.Vanillic acid and ferulic acid could be base-line separated in a50mmol/Lboraxbuffer(pH8.4)within8min.A300μm diameter carbon disk electrode was used as the working electrode positioned carefully opposite the outlet of the capillary in a wall-jet configuration at potential of0.80V(vs.SCE).There is an excellent linearity between peak current and analytes concentration in the range of5×10 -4 ～1×10 -6 mol/L and1×10 -3 ～1×10 -6 mol/L with the detection limits(S/N=3)of3.0×10 -7 and4.2×10 -7 mol/Lfor vanillic acid and ferulic acid,respectively.The relative standard deviations(RSD)of the peak currents of vanillic acid and ferulic acid were2.2%and2.8%(n=7),respectively.Recoveries of99%for vanillic acid and102.8%for ferulic acid were obtained(n=3).
出处
《分析测试学报》
CAS
CSCD
北大核心
2003年第6期95-97,共3页
Journal of Instrumental Analysis
