2.7 High performance liquid chromatography (HPLC) and related techniques: 2.7.2. Isolation of impurities by (semi)preparative HPLC

Publisher Summary Application of preparative and semi-preparative HPLC becomes necessary when the identification of an impurity cannot be carried out with acceptable certainty by means of the simple use of analytical (chromatographic, spectroscopic, hyphenated) techniques. Prior to the spectroscopic investigations, it is advisable to check once again the isolated material for identity and homogeneity. Identity checking should be done by the earlier discussed retention matching method. The peak purity test, performed with a diode-array detector could be a further verification that the sample does not contain other compounds with different UV spectra. After having elaborated the strategy and developed the HPLC methods, the next step is performing the isolation. The course of the HPLC separation and recovery process is the same in enrichment and purification in the case of overlapping band separations.