Kitagawa Fumihiko, Kiamiya Masato, Otsuka Koji
Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku. Kyoto 615-8510, Japan.
J Chromatogr B Analyt Technol Biomed Life Sci. 2008 Nov 1;875(1):323-8. doi: 10.1016/j.jchromb.2008.06.038.
Fused-silica capillaries were modified by the successively multiple ionic-polymer layer (SMIL) coating technique for a capillary electrochromatography (CEC) analysis of binaphthyl enantiomers. The SMIL coating capillaries consisting of three different polymers (A(+)-B(-)-C(+) coating) were prepared by the alternative deposition of positively charged chiral or achiral polymers and negatively charged DNA. Previous studies have indicated that DNA-cationic polypeptide or synthetic polymer complexes immobilized onto the inner surface of the capillary worked as the chiral stationary phases for 1,1'-binaphthyl-2,2'-diyl hydrogen phosphate (BNP). In this study, to investigate the chiral recognition mechanism and optimize the CEC separation condition in the DNA-cationic polymer coating, effects of the chirality of the polymer unit, the strand of DNA, and the number of layer pairs on the separation were investigated. It should be noted that, since single stranded DNA (ssDNA) was more suitable to immobilize cationic polymers than double stranded DNA, the ssDNA-cationic polymer immobilized capillaries gave a stable electroosmotic flow and reproducible CEC analyses. As a result, a poly(ethyleneimine)-ssDNA-protamine (Prt) coating provided the best chiral separation of BNP. The high separation performance of the prepared capillary is discussed in terms of DNA/polycations interaction.
采用连续多层离子聚合物层（SMIL）涂层技术对熔融石英毛细管进行改性，用于联萘对映体的毛细管电色谱（CEC）分析。由三种不同聚合物组成的SMIL涂层毛细管（A(+)-B(-)-C(+)涂层）通过带正电的手性或非手性聚合物与带负电的DNA交替沉积制备而成。先前的研究表明，固定在毛细管内表面的DNA - 阳离子多肽或合成聚合物复合物可作为1,1'-联萘-2,2'-二磷酸酯（BNP）的手性固定相。在本研究中，为了研究DNA - 阳离子聚合物涂层中的手性识别机制并优化CEC分离条件，研究了聚合物单元的手性、DNA链以及层数对分离的影响。需要注意的是，由于单链DNA（ssDNA）比双链DNA更适合固定阳离子聚合物，因此ssDNA - 阳离子聚合物固定化毛细管具有稳定的电渗流和可重复的CEC分析。结果，聚（乙烯亚胺）-ssDNA - 鱼精蛋白（Prt）涂层提供了BNP的最佳手性分离。从DNA/聚阳离子相互作用的角度讨论了所制备毛细管的高分离性能。
