Macià Alba, Borrull Francesc, Calull Marta, Aguilar Carme
Department of Analytical Chemistry and Organic Chemistry, University Rovira i Virgili, C/Marcel.li Domingo s/n, 43007 Tarragona, Spain.
J Chromatogr A. 2006 Jun 9;1117(2):234-45. doi: 10.1016/j.chroma.2006.03.076. Epub 2006 Apr 4.
Three on-column preconcentration techniques were compared to analyse a group of nonsteroidal anti-inflammatory drugs (NSAIDs) using micellar electrokinetic capillary chromatography (MEKC) under pH-suppressed electroosmotic flow (EOF) in water samples. The analysed drugs were ibuprofen, fenoprofen, naproxen, ketoprofen, and diclofenac sodium. The micellar background electrolyte (BGE) solution was formed by 75 mM sodium dodecyl sulfate (SDS), 40% (v/v) acetonitrile, and 25 mM sodium phosphate at pH 2.5. When this BGE solution was used the applied voltage was reversed, -10 kV, and the drugs were separated within 20 min. The on-column preconcentration modes, characterised all of them for the sample matrix removal out of the capillary by itself under a reverse potential at the same time as the EOF was reduced, were stacking with reverse migrating micelles (SRMM), stacking with reverse migrating micelles-anion selective exhaustive injection (SRMM-ASEI), and field-enhanced sample injection with reverse migrating micelles (FESI-RMM). The sensitivity was improved up to 154-, 263-, and 63-fold, respectively when it was calculated through the peaks height. The optimised methods were validated with spiked mineral water by combining off-line solid-phase extraction (SPE) and the proposed on-line sample stacking strategies. The detection limits (LODs) of NSAIDs in mineral water were at ng/L levels.
比较了三种柱上预富集技术，以在水样中pH抑制电渗流（EOF）条件下，使用胶束电动毛细管色谱法（MEKC）分析一组非甾体抗炎药（NSAIDs）。所分析的药物为布洛芬、非诺洛芬、萘普生、酮洛芬和双氯芬酸钠。胶束背景电解质（BGE）溶液由75 mM十二烷基硫酸钠（SDS）、40%（v/v）乙腈和25 mM磷酸钠在pH 2.5条件下形成。使用该BGE溶液时，施加电压为反向的-10 kV，药物在20分钟内分离。柱上预富集模式在降低EOF的同时，通过反向电位自身从毛细管中去除样品基质，分别为反向迁移胶束堆积（SRMM）、反向迁移胶束-阴离子选择性全量进样堆积（SRMM-ASEI）和反向迁移胶束场增强进样（FESI-RMM）。通过峰高计算时，灵敏度分别提高了154倍、263倍和63倍。通过离线固相萃取（SPE）与所提出的在线样品堆积策略相结合，对加标矿泉水验证了优化方法。矿泉水中NSAIDs的检测限为纳克/升水平。
