High-Performance Liquid Chromatography and Ion Chromatography

Abstract

We have learned that the first chromatographic technique was column chromatography. Since then, paper, thin-layer, and finally gas chromatography were developed. Now, many years later, we are going back to column chromatography! This seems like a strange sequence of events but there are good reasons for it. The original column chromatographic technique employed glass columns and either gravity flow or a slight vacuum to move the mobile phase through the column. This was also ``slow'' chromatography and ``hard to reproduce'' chromatography. It was, however, ``extremely flexible'' chromatography in that an almost unlimited variety of solvents and column packings could be used, neither of these completely available to paper, thin-layer, or gas chromatography. It was because of this recognized flexibility that scientists reexamined column chromatography.