15种氨基酸及2种多肽的毛细管电泳法定量分析

Quantitative Analysis of 15 Amino Acids and 2 Peptides by Capillary Electrophoresis

利用毛细管电泳建立了15种氨基酸及2种多肽的直接同时定量分析方法。方法简便易行,且线性范围宽、相对标准偏差低、精密度高、重现性好。最佳条件是:熔融石英毛细管60cm(50cm处检测窗口)×50μmi.d.;分离电压:+25kV;缓冲液:50mmol/L磷酸盐(pH=12.42,含少量甲醇);进样压力:0.5psi(3448Pa),进样时间:5.0s;分离温度:25℃;二极管阵列检测器波长:206nm。应用于玉米幼苗样品中氨基酸和多肽的定量,获得满意结果。

A general direct method to separate and quantify simultaneously 15 amino acids and 2 peptides was established by capillary electrophoresis（CE）.This method had a wide linear range,low relative standard deviation,high precision and perfect reproducibility.The following optimized apparatus condition was explored.A fused-silica capillary 60 cm（50 cm to detector） × 50 μm i.d.was used;working voltage of ＋ 25 kV was applied;background electrolyte was prepared of phosphate（50 mmol/L,pH 12.42） buffer with addition of methanol;and hydrodynamic injection of a sample （0.5 psi） during 5 sec was used at 25 ℃ with direct UV detection by diode array detector （DAD） at 206 nm.Quantitative analysis of a mixture of amino acids and peptides in maize seedlings can be achieved perfectly in this condition.