ABSTRACT
Chromatography is used for both analytical and preparative purposes. The mass of compound mixture processed can therefore vary enormously, e.g., from picogram (pg) to ton quantities. This is reflected in the size of the columns holding the chromatographic stationary phase or packing material. The purpose of packing a column is to obtain a chromatographically efficient and stable bed of stationary phase particles. The size of a packed liquid chromatography (LC) column should be determined by the sample size that has to be handled. Packing materials are characterized by two trends: packing materials are generally becoming smaller and the number of phases is growing ever more rapidly. Silica gel and silica gel-derivatized phases are by far the most used in LC at present. Great efforts are made to develop satisfactory alternatives also based on silica gel, so that proteins can be chromatographed on pressure-resistant packings. Packing pressure should be as high as compatible with column hardware, packing material and packing device.
