Anal Chem. 2010 Mar 15;82(6):2175-7. doi: 10.1021/ac100062t.
Extremely uniform packing of colloidal silica in capillaries is shown. Reversed-phase electrochromatograms of DiI-C(12) exhibit plate heights as low as 0.23 microm and a reduced plate height as low as 0.7, using 75 microm i.d. capillaries packed with 330 nm silica particles. The contribution from the A term is 0 +/- 20 nm in electrochromatography. The particles are shown to form colloidal crystals inside the capillaries. Optical images show Bragg diffraction, indicative of crystallinity. Scanning electron microscopy (SEM) images show face-centered cubic crystallinity, and the porosity is 0.25 +/- 0.01, which is in agreement with that for face-centered cubic crystals. The capillaries are fritless, and 100 microm i.d. capillaries packed with silica colloidal crystals withstand pressures of at least 12,400 psi.
展示了胶体二氧化硅在毛细管中极其均匀的填充。使用内径为 75μm 的毛细管填充 330nm 的二氧化硅颗粒,对 DiI-C(12)进行反相电色谱分析,得到的塔板高度低至 0.23μm,有效板高低至 0.7。在电色谱中,A 项的贡献为 0 ± 20nm。这些颗粒在毛细管内形成胶体晶体。光学图像显示布拉格衍射,表明具有结晶度。扫描电子显微镜 (SEM) 图像显示面心立方结晶度,孔隙率为 0.25 ± 0.01,与面心立方晶体一致。毛细管无烧结,填充胶体二氧化硅晶体的 100μm 内径毛细管可承受至少 12400psi 的压力。