Summary
The discovery of the capillary column was a milestone in the GC field. It has improved the separation efficiency and speed of gas chromatography analysis greatly. In this post, we will introduce the preparation and development of the GC capillary column.
Body
Preparation of capillary column
Efficient and prompt separation of capillary chromatography is mainly depended on the performance of capillary column, which is very important in chromatography.
Material of capillary column
As the development of the glass capillary column and the discovery of silica capillary column, the main ingredient of the capillary column is nearly glass and quartz tube with silica. With the good inert on the surface, thin wall and its flexible, quartz column is widely used. It also has replaced the glass column.
Stationary Phase
Stationary phase for the preparation of a capillary column includes two categories: one is the solid adsorbent, and the other is the stationary phase. The commonly used fixative are methyl polysiloxane, PEG-20M, methyl phenyl polysiloxane and cyanopropyl methyl polysiloxane. In recent years, some new fixative, such as liquid crystal polymer [6,7], aromatics [8], cyclodextrin derivatives [9, 10] and high-temperature stationary phase [11] have attracted more and more interest. Only with the help of good fixative, can we prepare a great capillary column. What’s more, the temperature coefficient of fixative viscosity should be as low as possible, in order to avoid the failure of liquid film.
Modification and coated technology of capillary column
In order to get the high-efficient capillary column for wettability of the inner surface of the tube, we should modify it according to the experience. There are two approaches for this step: chemistry and physical modification. Physical modification is also called roughening the inner wall, which is frequently used.
A good capillary column should have selective ability, high column efficiency, thermal stability and pillars inert. The selective ability of pillars is detected by the object to be separated. Different columns have different requirements.
Capillary chromatography has been used extensively in chromatographic analysis. High column efficiency and low loss are the direction of the future development of the capillary column.
Related services: