Malmquist G, Lundell N
Department of Analytical Chemistry, Uppsala University, Sweden.
J Chromatogr. 1992 Dec 25;627(1-2):107-24. doi: 10.1016/0021-9673(92)87191-a.
It has been shown earlier that the choice of displacing salt has a large effect on the retention in ion-exchange chromatography of proteins and peptides. The influence of different displacing salts cannot be predicted or quantitatively explained, owing to the current lack of an adequate theoretical framework. In this work a general characterization is made by using a considerable number of proteins and peptides and all displacing salts found feasible. Principal component analysis is used to interpret the large amount of data that is generated. The results of the analysis indicate that most of the retention variations are due to non-specific effects and can be explained by changes in the apparent gradient slope, i.e., the increase in elution strength per unit volume, and the elution strength of the starting buffer. This differs from the interpretation given earlier, where the selectivity changes were attributed to specific effects of the salts. However, as it is impossible to test all existing proteins and peptides, specific effects are still possible, but they might be less common than previously considered.
先前已经表明，置换盐的选择对蛋白质和肽在离子交换色谱中的保留有很大影响。由于目前缺乏适当的理论框架，不同置换盐的影响无法预测或定量解释。在这项工作中，通过使用大量蛋白质和肽以及所有可行的置换盐进行了全面表征。主成分分析用于解释所产生的大量数据。分析结果表明，大多数保留变化是由于非特异性效应，可以通过表观梯度斜率的变化来解释，即单位体积洗脱强度的增加以及起始缓冲液的洗脱强度。这与先前给出的解释不同，先前认为选择性变化归因于盐的特异性效应。然而，由于不可能测试所有现有的蛋白质和肽，特异性效应仍然可能存在，但可能比以前认为的要少见。
