Oefner P J
Department of Genetics, Stanford University, Stanford, CA 94305-5120, USA.
Electrophoresis. 1995 Jan;16(1):46-56. doi: 10.1002/elps.1150160111.
Anions commonly found in biological fluids such as chloride, citrate, phosphate, bicarbonate, lactate, aspartate and glutamate, were determined within 60 s by means of capillary zone electrophoresis and indirect UV detection using 10 mM of chromate, pH 8.0, as both carrier electrolyte and chromophore. The lower mass detection limit was 0.5 pmol. In order to avoid a gradual shift of the pH and, in consequence, drifting ionic mobilities due to the formation of hydroxyl ions at the cathode, 1 mM of 5,5-diethylbarbiturate was added to the background electrolyte. Moreover, fused silica capillaries were coated with a 0.0003% solution of hexadimethrine bromide for two minutes between runs to reverse electroendosmotic flow which otherwise would counteract the electrophoretic migration of the anions and, hence, increase time of analysis. It is concluded that charge-reversed capillary zone electrophoresis in concert with indirect UV detection is superior to ion chromatography and conductivity detection in the determination of inorganic and organic anions in biological fluids both with regard to selectivity, sensitivity and speed of analysis.
通过毛细管区带电泳和间接紫外检测法，在60秒内测定了生物流体中常见的阴离子，如氯离子、柠檬酸根离子、磷酸根离子、碳酸氢根离子、乳酸根离子、天冬氨酸根离子和谷氨酸根离子。使用10 mM的铬酸盐（pH 8.0）作为载体电解质和发色团。质量检测下限为0.5皮摩尔。为了避免pH值逐渐变化，以及由于在阴极形成氢氧根离子而导致离子迁移率漂移，在背景电解质中加入了1 mM的5,5 -二乙基巴比妥酸盐。此外，在每次运行之间，用0.0003%的溴化六甲双铵溶液对熔融石英毛细管进行两分钟的涂层处理，以逆转电渗流，否则电渗流会抵消阴离子的电泳迁移，从而增加分析时间。得出的结论是，在生物流体中无机和有机阴离子的测定方面，电荷反转毛细管区带电泳与间接紫外检测相结合，在选择性、灵敏度和分析速度方面优于离子色谱法和电导检测法。
