Rey M A
Dionex Corporation, Sunnyvale, CA 94085, USA.
J Chromatogr A. 2001 Jun 22;920(1-2):61-8. doi: 10.1016/s0021-9673(01)00638-0.
One of the advantages of ion chromatography [Anal Chem. 47 (1975) 1801] as compared to other analytical techniques is that several ions may be analyzed simultaneously. One of the most important contributions of cation-exchange chromatography is its sensitivity to ammonium ion, which is difficult to analyze by other techniques [J. Weiss, in: E.L. Johnson (Ed.), Handbook of Ion Chromatography, Dionex, Sunnyvale, CA, USA]. The determination of low concentrations of ammonium ion in the presence of high concentrations of sodium poses a challenge in cation-exchange chromatography [J. Weiss, Ion Chromatography, VCH, 2nd Edition, Weinheim, 1995], as both cations have similar selectivities for the common stationary phases containing either sulfonate or carboxylate functional groups. The task was to develop a new cation-exchange stationary phase (for diverse concentration ratios of adjacent peaks) to overcome limitations experienced in previous trails. Various cation-exchange capacities and column body formats were investigated to optimize this application and others. The advantages and disadvantages of two carboxylic acid columns of different cation-exchange capacities and different column formats will be discussed.
与其他分析技术相比，离子色谱法[《分析化学》，47 (1975) 1801]的优势之一在于可以同时分析多种离子。阳离子交换色谱法最重要的贡献之一是其对铵离子的灵敏度，而铵离子很难用其他技术进行分析[J. 魏斯，载于：E.L. 约翰逊（编），《离子色谱手册》，美国加利福尼亚州森尼韦尔市戴安公司]。在阳离子交换色谱法中，在高浓度钠离子存在的情况下测定低浓度铵离子是一项挑战[J. 魏斯，《离子色谱法》，VCH出版社，第2版，德国魏因海姆，1995]，因为这两种阳离子对含有磺酸根或羧酸根官能团的常见固定相具有相似的选择性。任务是开发一种新的阳离子交换固定相（用于不同浓度比的相邻峰），以克服之前试验中遇到的局限性。研究了各种阳离子交换容量和柱体形式，以优化此应用及其他应用。将讨论两种具有不同阳离子交换容量和不同柱形式的羧酸柱的优缺点。
