Ali Faiz, Cheong Won Jo
Department of Chemistry, Inha University, Namku, Incheon, South Korea.
J Sep Sci. 2014 Dec;37(23):3426-34. doi: 10.1002/jssc.201400811. Epub 2014 Oct 21.
Ground porous silica monolith particles with an average particle size of 2.34 μm and large pores (363 Å) exhibiting excellent chromatographic performance have been synthesized on a relatively large scale by a sophisticated sol-gel procedure. The particle size distribution was rather broad, and the d(0.1)/d(0.9) ratio was 0.14. The resultant silica monolith particles were chemically modified with chlorodimethyloctadecylsilane and end-capped with a mixture of hexamethyldisilazane and chlorotrimethylsilane. Very good separation efficiency (185,000/m) and chromatographic resolution were achieved when the C18 -bound phase was evaluated for a test mixture of five benzene derivatives after packing in a stainless-steel column (1.0 mm × 150 mm). The optimized elution conditions were found to be 70:30 v/v acetonitrile/water with 0.1% trifluoroacetic acid at a flow rate of 25 μL/min. The column was also evaluated for fast analysis at a flow rate of 100 μL/min, and all the five analytes were eluted within 3.5 min with reasonable efficiency (ca. 60,000/m) and resolution. The strategy of using particles with reduced particle size and large pores (363 Å) combined with C18 modification in addition to partial-monolithic architecture has resulted in a useful stationary phase (C18 -bound silica monolith particles) of low production cost showing excellent chromatographic performance.
通过一种复杂的溶胶 - 凝胶法大规模合成了平均粒径为2.34μm且具有大孔（363 Å）的地面多孔硅胶整体颗粒，该颗粒表现出优异的色谱性能。粒径分布相当宽，d(0.1)/d(0.9) 比率为0.14。所得的硅胶整体颗粒用氯二甲基十八烷基硅烷进行化学改性，并用六甲基二硅氮烷和氯三甲基硅烷的混合物进行封端。在不锈钢柱（1.0 mm×150 mm）中填充后，对五种苯衍生物的测试混合物评估C18键合相时，实现了非常好的分离效率（185,000/m）和色谱分辨率。发现优化的洗脱条件为70:30 v/v的乙腈/水，含0.1%的三氟乙酸，流速为25 μL/min。还对该柱在100 μL/min的流速下进行了快速分析评估，所有五种分析物在3.5分钟内洗脱，具有合理的效率（约60,000/m）和分辨率。使用粒径减小且具有大孔（363 Å）的颗粒，结合C18改性以及部分整体结构的策略，已产生了一种生产成本低且表现出优异色谱性能的有用固定相（C18键合硅胶整体颗粒）。
