HPLC Plants

BD Oomah, H Voldeng, JA Fregeau-Reid. Characterization of soybean proteins by HPLC. Plant Foods Hum Nutr 45 25 -263, 1994. 

OM Palomino, P Gomez-Serranillos, E Carretero, A Cases. Variation in the flavonoid content of Origanum x majoricum in different plant stages by HPLC. Plants Medica 63 584, 1997. 

Dihydrochelerythrine, Preparative HPLC plant N-methylflindersine extracts Silica gel 300x50 Et 0-hexane(l 9) EtOAc-hexane(1 4) 8... 

Figure 3.1 shows a scheme of an HPLC plant. The column contains a packing that is a dense array of porous or non-porous particles. Alternatively, the column is composed of a continuous bed, i.e. a porous piece called a monolith. 

Before injecting the first sample some general considerations have to be taken into account with regard to the design of the preparative chromatographic plant. All preparative HPLC plants consist, basically, of the same components (Fig. 5.1) a solvent and sample delivery system, the preparative column and a detection and fraction collection system. 

Section 6.2 presents various models for chromatographic columns. But it has to be kept in mind that these models only account for effects occurring within the packed bed. A HPLC-plant, however, consists of several additional equipment and fittings besides the column. Therefore, the effect of this extra column equipment has to be accounted for to obtain reasonable agreement between experimental results and process simulation. Peripheral equipment (for example pipes, injection system, pumps and detectors) causes dead times and mixing. Thus, it can contribute considerably to the band broadening measured by the detector. 

The upper part of Fig. 6.5 shows the standard set-up of an HPLC-plant. The injection of a rectangular pulse is performed via a three-way valve and a subsequent pump... 

Fig. 6.5 Comparison between process flow diagram and simulation flowsheet for an HPLC plant.

Surface-modified silica-based stationary phase packings in chromatography are mostly characterized under isocratic conditions. The employed tests help to assess chromatographic parameters and make it possible to compare different stationary phases. Robustness, reproducibility, and easy handling are the requirements for such tests. It is also important to separate extra-column effects in order to be able to evaluate the column itself rather than the whole HPLC plant system. 

Dunaliella salina DGTS and its individual molecular species by HPLC, Plant Sci. 42 83 ( 1985). 

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