The Purific fractionation system performs both sample injection and fraction collection. Dual arms prevent cross-contamination. The unit collects in up to 1000 test tubes in semi-prep mode, or 24 microplates for analytical applications. The sample preparation, injection, collection and fraction post-processing system incorporates PEAK HARVESTER software, which facilitates the building of sampling sequences by selecting samples from a layout screen, and pre-process sample and/or post-process fractions.