Development of porous silica rod columns for higher performance of HPLC

(1)制备了三种衍生化为C18相的整体硅胶色谱柱。(2)具有微米级硅胶骨架和微米级大孔的连续硅胶柱在小骨架的基础上具有更高的效率和更低的压降。(3)模压成型的聚四氟乙烯热收缩管覆盖的硅棒色谱柱，在流动相线速度较高时，流动阻力比传统填充柱低近一个数量级，柱效高得多。(3)模压成型的聚四氟乙烯热收缩管覆盖的硅胶棒柱，在流动相线速度较高的情况下，流动阻力降低了近一个数量级，柱效显著提高。(3)模塑成型聚四氟乙烯热收缩管覆盖的硅胶棒柱，在流动相线速度较高的情况下，5μm颗粒填充柱具有更高的效率和更低的压降。4)在熔融石英毛细管中制备的硅胶整体柱具有更低的压降。(5)毛细管整体柱的柱效低于在模子中制备的柱效率，尤其是在高线速度下，这可能是因为存在更大的通孔。(6)作为原型产品的聚醚醚酮覆盖的硅胶棒显示出比其他整体硅胶柱更高的流动阻力，但它们仍然表现出比流行的5μm反相高效液相色谱柱更高的柱效和更低的压降。(7)毛细管中的硅胶整体柱也可以用于毛细管电泳色谱分离，从而产生更高的柱效率。(8)硅胶整体柱在多肽分离方面的性能比目前的高效液相色谱填料要高得多。将分离时间缩短三倍或更多。(9)硅胶整体柱在结构和色谱性能方面的优化和表征将导致用于更高性能的高效液相色谱柱和电色谱柱的开发。(10)整体柱将提供可与超高压液相色谱或CEC相媲美的高性能(使用现有的高效液相色谱仪器)。

(1) Three types of monolithic silica columns derivatized to C18 phase were prepared.(2) The continuous silica columns having micrometer-size silica skeletons and micrometer-size through-pores gave higher efficiency and much lower pressure drop on the basis of the small-sized skeletons with much higher through-pore size/skeleton size ratios than conventional particle-packed columns.(3) Silica rod columns prepared in a mold and covered with heat shrinking PTFE tubing showed nearly an order of magnitude lower flow resistance and much higher column efficiency than conventional columns packed with 5 μm particles at high linear velocity of the mobile phase.(4) Silica monoliths prepared in a fused silica capillary showed even lower pressure drop.(5) The column efficiency of the capillary monolith was lower than those prepared in a mold, especially at high linear velocity, presumably due to the presence of much larger through-pores.(6) The silica rods covered with PEEK to be a prototype product showed higher flow-resistance than the other monolithic silica columns, but they still showed higher column efficiency and lower pressure drop than popular 5μm silica packing materials for reversed-phase liquid chromatography.(7) The silica monolith in capillary can also be used in CEC to generate much higher column efficiency.(8) The silica monoliths showed much higher performance for polypeptide separations than current HPLC packing materials, providing the shortening of separation time by a factor of three or more.(9) The optimization and characterization of silica monoliths in terms of structural and chromatographic properties will lead to the development of columns for HPLC and CEC of much higher performance.(10) The monolithic columns will provide high performance (with current HPLC instrumentation) that is comparable with that of ultrahigh pressure liquid chromatography or CEC.