Castagnola M, Cassiano L, Messana I, Paci M, Rossetti D V, Giardina B
Istituto di Chimica Biologica dell'Università di Cagliari, Italy.
J Chromatogr A. 1996 May 31;735(1-2):271-81. doi: 10.1016/0021-9673(95)00963-9.
The use of 2,2,2-trifluoroethanol-water mixtures for peptide separations by capillary zone electrophoresis (CZE) displays some advantages over aqueous solutions. First, the increase in viscosity reduces and stabilizes the running current and facilitates heat dispersion, with a consequent improvement in the number of theoretical plates. Second, the decrease in the dielectric constant leads to a modification of the dissociation constants of the ionizable groups. The consequence is a change in selectivity that, for several favourable peptide pairs, provides an increase in resolution. Third, the interaction trifluoroethanol with the peptide modifies the Stokes radius in a manner strongly dependent on the peptide sequence. This can also be utilized for an increase in CZE performance. Fourth, the structural properties of 2,2,2-trifluoroethanol are particularly useful for an improvement in the separation of large apolar peptides. Finally, the use of trifluoroethanol strongly stabilizes the capillary coating.
使用2,2,2-三氟乙醇-水混合物通过毛细管区带电泳（CZE）进行肽分离比使用水溶液具有一些优势。首先，粘度的增加降低并稳定了运行电流，促进了热分散，从而提高了理论塔板数。其次，介电常数的降低导致可电离基团解离常数的改变。结果是选择性发生变化，对于几个有利的肽对，分辨率有所提高。第三，三氟乙醇与肽的相互作用以强烈依赖于肽序列的方式改变了斯托克斯半径。这也可用于提高CZE性能。第四，2,2,2-三氟乙醇的结构特性对于改善大的非极性肽的分离特别有用。最后，使用三氟乙醇可强烈稳定毛细管涂层。
