Ohman M, Wang H, Hamberg M, Blomberg L G
Department of Chemistry, Karlstad University, Sweden.
Electrophoresis. 2001 Apr;22(6):1163-9. doi: 10.1002/1522-2683()22:6<1163::AID-ELPS1163>3.0.CO;2-M.
A micellar electrokinetic chromatography (MEKC) method has been developed for the direct resolution of divinyl ether type of hydrophobic fatty acid isomers. The fatty acid isomers resolved include colneleic acid (CL), colnelenic acid (CLn), 14(Z)-etheroleic acid (14(Z)-EL), 14(Z)-etherolenic acid (14(Z)-Eln), 11(Z)-etheroleic acid (11(Z)-EL), 11(Z)-etherolenic acid (11(Z)-Eln), etheroleic acid (EL) and etherolenic acid (Eln). These fatty acid isomers differ in number, position and spatial arrangement of the double bonds and the position of the ether oxygen. A central composite design was employed for the optimization of the key variables of the separation, namely the concentrations of sodium dodecyl sulfate (SDS) and organic modifiers. The use of micelles combined with an organic modifier in the background electrolyte made it possible to dissolve and separate relatively hydrophobic fatty acid isomers, and to achieve high separation efficiency. Using heptakis-(2,3-dimethyl-6-sulfato)-beta-cyclodextrin (HDMS-beta-CD) as a buffer additive, complete separation of the examined eight divinyl ethers was achieved. Separation efficiencies up to 5 x 10(5) theoretical plates/m were achieved under optimized conditions. Direct UV was applied for detection of the fatty acids. The results were compared with those obtained from high-performance liquid chromatography (HPLC) separation.
已开发出一种胶束电动色谱（MEKC）方法，用于直接拆分二乙烯基醚型疏水脂肪酸异构体。拆分出的脂肪酸异构体包括结肠油酸（CL）、结肠亚油酸（CLn）、14(Z)-醚油酸（14(Z)-EL）、14(Z)-醚亚油酸（14(Z)-Eln）、11(Z)-醚油酸（11(Z)-EL）、11(Z)-醚亚油酸（11(Z)-Eln）、醚油酸（EL）和醚亚油酸（Eln）。这些脂肪酸异构体在双键的数量、位置和空间排列以及醚氧的位置上存在差异。采用中心复合设计对分离的关键变量，即十二烷基硫酸钠（SDS）和有机改性剂的浓度进行优化。在背景电解质中使用胶束与有机改性剂相结合，使得相对疏水的脂肪酸异构体能够溶解和分离，并实现了高分离效率。使用七（2,3-二甲基-6-硫酸根）-β-环糊精（HDMS-β-CD）作为缓冲添加剂，实现了所检测的八种二乙烯基醚的完全分离。在优化条件下，分离效率高达5×10⁵理论塔板数/米。采用直接紫外检测脂肪酸。将结果与高效液相色谱（HPLC）分离得到的结果进行了比较。
