Ali Ashraf, Ali Faiz, Cheong Won Jo
Department of Chemistry, Inha University, Incheon, 22212, South Korea.
Department of Chemistry, University of Malakand, KPK, Pakistan.
J Chromatogr A. 2017 Nov 24;1525:79-86. doi: 10.1016/j.chroma.2017.10.014. Epub 2017 Oct 6.
The sedimentation procedure has been adopted in production of ground silica monolith particles to improve chromatographic separation efficiency of the resultant phase. First, silica monolith particles have been successfully prepared in a large scale by a sol-gel process followed by grinding. The particles after calcination were separated by sedimentation into three zones using an Imhoff sedimentation cone. The particles of the bottom zone were derivatized with a C18 ligand and end-capped. The sedimentation process was found to not only eliminate troublesome minute particles but also narrow down the particle size distribution. The resultant phase was packed in glass lined stainless steel micro-columns. The average number of theoretical plates (N) of the columns for a test mixture was 47,000 and 29,300 for the 300 and 150mm columns (1mm internal diameter), corresponding to 157,000/m and 195,000/m, respectively.
在生产硅胶整体颗粒时采用了沉降法，以提高所得固定相的色谱分离效率。首先，通过溶胶 - 凝胶法然后研磨，成功大规模制备了硅胶整体颗粒。煅烧后的颗粒使用英霍夫沉降锥通过沉降分离为三个区域。底部区域的颗粒用C18配体进行衍生化并封尾。发现沉降过程不仅可以去除麻烦的微小颗粒，还可以缩小粒径分布。将所得固定相填充到玻璃衬里的不锈钢微柱中。对于测试混合物，300mm和150mm柱（内径1mm）的柱理论塔板数（N）平均值分别为47,000和29,300，分别对应于157,000/m和195,000/m。
