毛细管电泳大体积进样在柱复合富集技术

On-line and Dual Pre-concentration Technique for Large Volume Injection in Capillary Electrophoresis

提出场放大进样和酸堆积结合的大体积样品复合富集方法,实现了毛细管电泳对高盐样品中阳离 子的有效富集和分离。向样液中添加70%(V/V)乙腈,场放大进样600s后,电动注入强酸做酸堆积,预富集 样品带用毛细管区带电泳分离仍能获得满意的分离度。此法的富集倍数约为常规电动进样的800倍。普萘

A dual pre-concentration method combining acetonitrile field-amplified injection with acid stacking for large-volume sampling was proposed in capillary electrophoresis in this paper. The pre-concentration method can achieve effective concentration and separation of cations in high-salt sample solutions containing 150 mmol/L NaCl. By adding 70% (V/V) acetonitrile into sample solution, performing field-amplified injection for 600 s at 10 kV, injecting o.1 mol/L HCl for 600 s at 15 kV, and then separating by capillary zone electroporesis at 15 kV, a satisfactory resolution can still be obtained. In contrast to conventional electrokinetic injection, the sensitivity enhancement of capillary electrophoresis-ultraviolet spectrophotometry was about 800-fold. Detection limit of propranolol and metoprolol was 1 X 10(-4) and 7 X 10(-4) mg/L, respectively.