SOME SPECIFIC PROBLEMS IN THE PRACTICE OF PREPARATIVE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

The practice of preparative high-performance liquid chromatography (PL C) is reviewed. Special attention is paid to problems with the use of this method in research and development which are insignificant or unf amiliar on an analytical scale. PLC column concepts, stability and rel ated packing procedures are discussed. Guidelines to column size selec tion and optimum use are presented. The paramount importance of high r esolution for successful PLC separation is stressed and the effect of friction heat generated by viscous flow on the column performance is d escribed. The significance of sufficient sample solubility in the mobi le phase is discussed. Possible deleterious effects of the use of stro ng solvents with viscosities different from that of the mobile phase a re considered. The packing solubility is shown to influence product pu rity; various product isolation procedures are discussed and the use o f solid-phase extraction is recommended.