Matyska M T, Pesek J J, Boysen R I, Heam M T
Department of Chemistry, San Jose State University, California 95192-0101, USA.
Anal Chem. 2001 Nov 1;73(21):5116-25. doi: 10.1021/ac010384r.
In this paper, we report on investigations related to the performance characteristics of two different types of etched chemically (n-octadecyl- and cholesterol-) modified capillaries in the open tubular format of capillary electrochromatography (CEC) for the analysis of synthetic peptides. The results confirm that the nature of the surface chemistry used to modify the capillary wall and type of chemically bonded group employed can affect the selectivity as well as the resolution of peptide samples. The results are consistent with the participation of selective peptide interactions with the bonded phase, although other factors, such as the morphology of the capillary wall surfaces, appear to be also involved. Moreover, several surprising observations related to peptide-specific multi-zoning effects have been observed. Additional experimental variables that can also be utilized to affect the retention of peptides in this approach to OTCEC include the type and percentage of organic solvent modifier employed in the eluent and the pH of the buffer system. To evaluate the reproducibility of different batches of the n-octadecyl- and cholesterol-modified capillaries and the stability of the chemically modified surface, the OTCEC selectivity and peak shape behavior of two small basic molecules (serotonin and tryptamine) and two proteins (turkey and chicken lysozyme) were also investigated. Finally, the use of the "bubble" cell technology for creating the detector window has been shown to provide significantly higher detection sensitivity with peptides, as compared with the conventional capillary format.
在本文中，我们报告了有关两种不同类型的化学蚀刻（正十八烷基和胆固醇修饰）毛细管在毛细管电色谱（CEC）开放管状模式下用于合成肽分析的性能特征的研究。结果证实，用于修饰毛细管壁的表面化学性质以及所采用的化学键合基团类型会影响肽样品的选择性和分离度。结果与肽与键合相之间的选择性相互作用有关，尽管其他因素，如毛细管壁表面的形态，似乎也有参与。此外，还观察到了一些与肽特异性多区域效应相关的惊人现象。在这种开管毛细管电色谱方法中，还可用于影响肽保留的其他实验变量包括洗脱液中所用有机溶剂改性剂的类型和百分比以及缓冲系统的pH值。为了评估不同批次的正十八烷基和胆固醇修饰毛细管的重现性以及化学修饰表面的稳定性，还研究了两种小碱性分子（血清素和色胺）以及两种蛋白质（火鸡和鸡溶菌酶）的开管毛细管电色谱选择性和峰形行为。最后，与传统毛细管形式相比，已证明使用“气泡”池技术创建检测窗口可显著提高对肽的检测灵敏度。
