Ahumada I, Mendoza J, Escudero P, Mossert K, Ascar L
Universidad de Chile, Facultad de Ciencias Químicas y Farmacéuticas, Santiago.
J AOAC Int. 2001 Jul-Aug;84(4):1057-64.
Capillary zone electrophoresis with indirect UV detection at 254 nm was found to be suitable for the determination of organic acids and phosphate in aqueous extracts of soil. The best support electrolyte solution was found to be 10 mM p-hydroxybenzoic acid with 0.5 mM tetradecyltrimethylammonium bromide to reverse electroosmotic flow. This methodology was tested with 9 analytes found in soils: acetate, citrate, formate, phosphate, lactate, oxalate, pyruvate, succinate, and tartrate. The results obtained show that the methodology is adequate for most of the analytes. The sensitivity to oxalate and citrate was low, and the high concentrations of major inorganic anions interfered with the detection of the former. The methodology was applied to the analysis of aqueous extracts of soil samples. Formate, phosphate, lactate, and acetate anions were detected in most of the samples.
结果发现，采用254nm间接紫外检测的毛细管区带电泳法适用于测定土壤水提取物中的有机酸和磷酸盐。最佳的支持电解质溶液是含有0.5mM十四烷基三甲基溴化铵的10mM对羟基苯甲酸，以逆转电渗流。该方法用土壤中发现的9种分析物进行了测试：乙酸盐、柠檬酸盐、甲酸盐、磷酸盐、乳酸盐、草酸盐、丙酮酸盐、琥珀酸盐和酒石酸盐。所得结果表明，该方法适用于大多数分析物。对草酸盐和柠檬酸盐的灵敏度较低，主要无机阴离子的高浓度干扰了前者的检测。该方法应用于土壤样品水提取物的分析。大多数样品中检测到了甲酸盐、磷酸盐、乳酸盐和乙酸盐阴离子。
