芳香胺的碱坝聚焦-毛细管电泳分析

建立了碱坝聚焦-毛细管电泳方法, 实现了一些芳香胺的高灵敏检测. 该方法操作简单, 只需在大体积进样前先泵入一段NaOH溶液. 当进样5 cm长时, 间苯二胺、邻苯二胺及三聚氰胺的检出限可分别降至0.1, 0.05和0.05 μmol/L, 灵敏度比常规进样提高了100倍. 在2个量级浓度范围内, 各分析物峰面积与浓度具有良好的线性关系, 线性相关系数大于0.999. 该法可用于分析染发剂样品.

Online Base Barrage Focusing and Capillary Electrophoresis of Aromatic Amines

A base barrage focusing approach online-coupled to capillary electrophoresis(CE) was developed and used for the analysis trace aromatic amines. To realize online focusing, a plug of 200 mmol/L NaOH was introduced in front of a sample zone just before electrophoresis. This method is facile and can be conducted on any CE system. After some optimization of the base barrage length and concentration, the method could be applied to the assay of m-phenylenediamine, o-phenylenediamine and melamine, with limits of detection down to 0.10 μmol/L m-phenylenediamine, 0.05 μmol/L o-phenylenediamine and 0.05 μmol/L melamine respectively, producing about 100-fold increase of sensitivity compared with the common method. Linear relationship was found between the peak area and sample concentration over two grades of magnitude, with linear correlation coefficients better than 0.999. As a validation, the method has also been applied to the analysis of a commercial hair dye, with the recovery between 94% and 97%.