Liquid-solid chromatography sorbent selection

Figure 6.13. Separation mode selection guide for TLC. LSC = liquid-solid chromatography on an inorganic oxide adsorbent BPC = liquid-solid chromatography on a chemically-bonded sorbent RPC = reversed-phase chromatography with a water-containing mobile phase and chemically-bonded stationary phase IPC = ion-pair chromatography with reversed-phase separation conditions and PC = precipitation chromatography. (From ref. [151] Elsevier)...

Solid-phase extraction (SPE) is based on low-pressure liquid chromatography, where a short column is filled with an adsorbent. The separation mechanisms are based on the intermolecular interactions among analyte molecules and functional groups of sorbent. The choice of eluent is made by the relationship between the eleutropic value (2°) and the analyte polarity. SPE is fast, selective, and economical if compared with the extraction methods described previously. It can be applicable to both nonpolar and polar analytes, but both matrix and analyte must be in the liquid state. 

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