Sintered thin-layer chromatography

Abstract

A new type of thin-layer chromatographic (TLC) plates, “sintered-glass thin-layer plates”, was prepared, the layer of which consists of silica gel, alumina, Kieselguhr or another porous adsorbent, fixed with sintered glass. These sintered plates are mechanically stable, heat- and acid resistant, and can be used in the same way as the usual laboratory-prepared or commercial TLC plates. It appears that the nature of the binder for the adsorbent particles does not essentially affect the separation process that occurs on the surface of the adsorbents. The sintered plates do not contain organic binders and are resistant to, e.g., heating after being sprayed with corrosive reagents. The developed sintered plates can be regenerated readily by soaking in cleaning solutions, washing with water and reactivating by heating. The reproducibility of chromatographic separations is further improved by recycled use of the sintered plates. It was also discovered that TLC using sintered rods with flame-ionization detection is very useful for qualitative and quantitative analyses of organic compounds. The method of preparation of the sintered plates and rods, and chromatographic separation data of various organic and inorganic compounds on these sintered materials, are presented. “Welding” mechanisms among adsorbent, binder and support, and thermal stability of the adsorbent at “welding” conditions are discussed.