Institut des Biomolécules Max Mousseron (IBMM, UMR 5247 CNRS-Université de Montpellier 1-Université de Montpellier 2), place Eugène Bataillon, case courrier 1706, 34095 Montpellier Cedex 5, France.
Anal Chem. 2010 Jan 1;82(1):394-9. doi: 10.1021/ac902211f.
This study deals with the separation by capillary zone electrophoresis (CE) of hardly soluble synthetic polypeptides such as poly(L-alanine). The characterization of the molar mass distribution of these polypeptides with neutral lateral chain is a prerequisite for a good understanding of the relationship between their structure and their biological activity. Nevertheless, these polypeptides are hardly soluble in a limited number of solvents such as strong acids (trifluoroacetic acid, methanesulfonic acid) and hexafluoroisopropanol (HFIP). Highly resolutive separations of end-charged hydrophobic alanine oligomers (up to 110 residues) were obtained by CE in a mixed hydro-organic HFIP/water solvent system under optimal conditions. The analyzed polyalanines possess a single positive charge on the N-terminus of their chain, and the potential negative charge at the C-terminus of their chain is suppressed by replacement of C-terminal alanine for alaninol. A careful optimization of the different constituents of the electrolyte (HFIP content, nature and concentration of the acid, nature and concentration of the cellulose derivative) was required to limit solute adsorption onto the capillary wall and to achieve the characterization of the entire molar mass distribution.
本研究采用毛细管区带电泳（CE）分离难溶性合成多肽，如聚（L-丙氨酸）。这些具有中性侧链的多肽的分子量分布的表征是了解其结构与生物活性之间关系的前提。然而，这些多肽在少数溶剂中难溶，如强酸（三氟乙酸、甲磺酸）和六氟异丙醇（HFIP）。在最佳条件下，通过在 HFIP/水混合水有机溶剂系统中进行 CE，可以对末端带电荷的疏水性丙氨酸低聚物（多达 110 个残基）进行高分辨率分离。分析的聚丙氨酸在其链的 N 末端带有一个正电荷，而其链的 C 末端的潜在负电荷通过用丙氨醇取代 C 末端的丙氨酸而被抑制。需要仔细优化电解质的不同成分（HFIP 含量、酸的性质和浓度、纤维素衍生物的性质和浓度），以限制溶质在毛细管壁上的吸附，并实现整个分子量分布的表征。
