Jiangsu Key Laboratory of Environmental Materials and Environmental Engineering, College of Chemistry and Chemical Engineering, Yangzhou University, Siwangting Road 180, Yangzhou 225002, Jiangsu, China.
J Chromatogr A. 2010 Oct 15;1217(42):6588-94. doi: 10.1016/j.chroma.2010.08.057. Epub 2010 Sep 16.
This paper reports on a new strategy to coat fused silica capillaries through ionic adsorption of gold nanoparticles (AuNPs) on a polyelectrolyte multilayer (PEM) modified capillary wall. The coating was constructed in situ by alternating rinses with positively charged poly(diallydimethylammonium chloride), negatively charged poly(sodium-4-styrenesulfonate), and positively charged AuNPs. After self-assembly of n-octadecanethiol onto the surface of AuNPs, the modified capillary was investigated as a new medium for the separation of neutral analytes and proteins in open-tubular capillary electrochromatography (OT-CEC). The surface coverage of the capillary wall was increased using the high density of AuNPs which were dynamically capped with 4-dimethylaminopyridine (DMAP). The chromatographic performance of the column coated with positively charged AuNPs was remarkably improved compared with a column modified with negatively charged AuNPs. The coating was robust over more than 810 runs in this study and also showed high stability against 0.01 M NaOH, 0.01 M HCl, and electrolyte concentrations up to 70 mM. The run-to-run, day-to-day, and capillary-to-capillary reproducibilities of electroosmotic flow were satisfying with relative standard deviation values of less than 1% in all cases. The AuNP-coated PEM modified capillary column not only showed good performance for neutral analytes but also was suitable for the analysis of both basic and acidic proteins.
本文报道了一种新的策略，通过在聚电解质多层（PEM）修饰的毛细管壁上离子吸附金纳米粒子（AuNPs）来涂覆熔融石英毛细管。该涂层通过交替用带正电荷的聚（二烯丙基二甲基氯化铵）、带负电荷的聚（4-苯乙烯磺酸钠）和带正电荷的 AuNP 冲洗原位构建。在 AuNP 表面自组装正十八硫醇后，研究了修饰后的毛细管作为在开管毛细管电色谱（OT-CEC）中分离中性分析物和蛋白质的新型介质。通过 AuNPs 的高密度动态封端 4-二甲氨基吡啶（DMAP），增加了毛细管壁的表面覆盖率。与用带负电荷的 AuNP 修饰的柱相比，涂覆带正电荷的 AuNP 的柱的色谱性能得到了显著改善。在本研究中，该涂层经过超过 810 次运行仍然稳定，并且对 0.01 M NaOH、0.01 M HCl 和高达 70 mM 的电解质浓度也具有高稳定性。在所有情况下，电渗流的运行间、日间和毛细管间重现性的相对标准偏差值均小于 1%，令人满意。AuNP 涂覆的 PEM 修饰毛细管柱不仅对中性分析物表现出良好的性能，而且还适用于分析碱性和酸性蛋白质。
