Engström A, Andersson P E, Josefsson B, Pfeffer W D
Department of Analytical Chemistry, Arrhenius Laboratories for Natural Sciences, Stockholm University, Sweden.
Anal Chem. 1995 Sep 1;67(17):3018-22. doi: 10.1021/ac00113a041.
A new precolumn reagent for amino acid determination, 2-(9-anthryl)ethyl chloroformate (AEOC), was introduced to obtain higher sensitivity in two capillary separation techniques, liquid chromatography (LC) and electrophoresis (CE). The chromophore in the (9-fluorenyl)methyl chloroformate (FMOC) reagent was replaced by anthracene, which resulted in a reagent with very high molar absorptivity (epsilon 256 = 180,000 L mol-1 cm-1). This permits AEOC-tagged species to be detected at nanomolar levels with UV absorbance detection in standard 50-microns-i.d. fused silica capillaries. Weaker absorption bands match the UV argon laser lines of 351 and 368 nm, which allows for convenient laser-induced fluorescence (LIF) detection. In this mode, picomolar limits of detection are obtained. In addition to measuring the limits of detection, we examined micellar electrokinetic chromatography, free solution capillary electrophoresis, and packed capillary LC and compared these methods regarding the separation of amino acids.
一种用于氨基酸测定的新型柱前试剂，即2-(9-蒽基)氯甲酸乙酯(AEOC)，被引入以在液相色谱(LC)和电泳(CE)这两种毛细管分离技术中获得更高的灵敏度。(9-芴基)氯甲酸甲酯(FMOC)试剂中的发色团被蒽取代，这产生了一种具有非常高摩尔吸光系数(ε256 = 180,000 L·mol-1·cm-1)的试剂。这使得在标准内径为50微米的熔融石英毛细管中，通过紫外吸光度检测能够检测到纳摩尔水平的AEOC标记物。较弱的吸收带与351和368 nm的紫外氩激光线相匹配，这便于进行激光诱导荧光(LIF)检测。在这种模式下，可获得皮摩尔级的检测限。除了测量检测限外，我们还研究了胶束电动色谱、自由溶液毛细管电泳和填充毛细管LC，并比较了这些方法在氨基酸分离方面的情况。
