Formamide as an organic modifier in MEKC with SDS
Formamide as an organic modifier in MEKC with SDS
复制标题
甲酰胺作为 MEKC 中的有机改性剂与 SDS
DOI：
10.1002/elps.200800329
复制
发表时间：
2009
期刊：
影响因子：
2.9
通讯作者：
E. Kenndler
中科院分区：
文献类型：
--
作者：
A. Téllez;E. Kenndler
研究了以十二烷基硫酸钠（SDS）为洗涤剂，甲酰胺（FA）作为改进剂对胶束电动色谱保留值的影响。一系列的烷基苯酮和两性离子荧光化合物作为FA和SDS浓度的函数的流动性被确定用于此目的。缓冲电解质为硼酸盐，pH 9.23，总离子强度为50 mM。流动性对FA含量的依赖性-高达63%w/w -的BGE（在10 mM SDS）允许的结论是，胶束是不稳定的，CMC被转移到更高的值。在含33%FA或更高的体系中，不再存在胶束，所有化合物的保留因子趋于零。在含有27%v/v FA的MEKC系统中，SDS的CMC从具有相同缓冲液组成的含水BGE中的2.4 mM增加到9.7 mM，这一行为与无电解质FA-水系统相反。自由分析物的分配常数和分析物和洗涤剂单体之间的加合物的形成常数（假设1：1化学计量）来自SDS浓度的依赖性的流动性。此外，所涉及的平衡扩展的分析物-单体加合物之间的水相和胶束相的分配，以及推导出相应的分配常数。两性离子化合物的分区的程度的选择性变化进行了观察。在一般情况下，所有的结合常数减少后，添加FA，但在不同程度上。虽然分析物-单体缔合物的结合常数仅受到轻微影响，但发现其分配到胶束中的最明显的减少。
The effect of formamide (FA) as a modifier on the retention in MEKC with SDS as the detergent was investigated. The mobility of a series of alkylphenones and of a zwitterionic fluorescent compound as a function of the FA and the SDS concentration was determined for this purpose. Buffering electrolyte was borate, pH 9.23, with total ionic strength of 50 mM. The dependence of the mobility on the FA content – up to 63% w/w – of the BGE (at 10 mM SDS) allows the conclusion that the micelles are destabilized, and the CMC is shifted to higher values. In the system containing 33% FA or more no micelles are present anymore, and the retention factors of all compounds tend to zero. In an MEKC system with 27% v/v FA the CMC of SDS is increased from 2.4 mM in the aqueous BGE with the same buffer composition to 9.7 mM, a behavior that is in contrast to electrolyte‐free FA–water systems. The partition constants of free analytes and the formation constants of the adduct between analyte and detergent monomer (assuming 1:1 stoichiometry) were derived from the dependence of the mobility on the SDS concentration. In addition, the involved equilibria were extended by that from the distribution of the analyte–monomer adduct between aqueous and micellar phase, and the according partition constants were derived as well. A selective change in the extent of partitioning was observed for the zwitterionic compound. In general, all binding constants were decreased upon addition of FA, though to a different extent. Although the binding constants of the analyte–monomer associate were only slightly influenced, the most pronounced decrease is found for their partitioning into the micelles.
可电离化合物胶束电动色谱的计算机辅助建模、预测和多因素优化。
影响因子：
7.4
作者：
Quang,C;Strasters,JK;Khaledi,MG
通讯作者：
Khaledi,MG
影响因子：
7.4
作者：
KHALEDI, MG;SMITH, SC;STRASTERS, JK
通讯作者：
STRASTERS, JK