Column selection for comprehensive multidimensional ion chromatography

Multidimensional and Comprehensive Liquid Chromatography

In this month’s “Column Watch,” Ron Majors discusses advances in multidimensional chromatography and comprehensive multidimensional chromatography. These techniques are well suited for the separation of complex samples. Although GC GC is fairly well developed, LC LC is in its infancy. But with fast LC columns, based on monoliths, superficially porous particles, and short sub-2m particle columns...

Determination of ammonium in seawater by column-switching ion chromatography.

A system which combines column switching and concentration was developed. A binary eluent mechanism was developed to study the effect of high sample concentration matrix on retention time shifts of the trace analyte. Separation conditions were chosen according to this mechanism to reduce the retention time shift of ammonium in the presence of high concentration sodium ion: high concentration su...

Technology of multidimensional gas chromatography (MDGC) and comprehensive two-dimensional gas chromatography (GC×GC)

The term ‘dimension’ in the above titles refers to the use of a ‘dimension of chromatography’ – or put more simply, a column – or for multidimension – two or more columns. In the broad sense, a ‘dimension of analysis’ is any technique that provides independent analysis capability. So FTIR, MS, and GC are discrete dimensions; they can be operated independently to provide some measure of analysis...

Column Liquid Chromatography

Comprehensive two-dimensional high-performance liquid chromatography system with immobilized liposome chromatography column and reversed-phase column for separation of complex traditional Chinese medicine Longdan Xiegan Decoction.

A comprehensive two-dimensional HPLC system with an immobilized liposome chromatography (ILC) column in conjunction with an RP column (in tandem) was developed for the screening and analysis of the membrane-permeable compounds in a traditional Chinese medicine prescription Longdan Xiegan Decoction (LXD). More than 50 components in LXD were resolved using the developed separation system. Eight f...