An overview of recent progress in elution mode of counter current chromatography

Countercurrent chromatography (CCC) is a developing chromatographic technique that achieves separation based on the distribution of the target in an immiscible biphasic or multiphasic solvent system. In the past decades, this technique has advanced greatly in application and theory. This overview is mainly focused on the development of elution modes, which have been easily achieved with the classical CCC apparatus in recent years. It includes gradient elution, dual-mode elution, multiple dual-mode elution, recycling elution, extrusion elution, cocurrent elution and pH zone refining. The basic principles of each elution mode are described in detail and then summarized. The comparison and the scope of application of these elution modes are also discussed. The financial support of the National Natural Science Foundation of China (NSFC No. 21175142 and No. 21505144) and Open Fund of Key Laboratory of Chemistry of Northwestern Plant Resources of the Chinese Academy of Sciences (No. CNPR-2011kfkt-02) is acknowledged. Dr X.-Y Huang is also grateful for the financial support from CAS to undertake overseas academic visits; he also acknowledges the Advanced Bioprocessing Centre at Brunel University, UK, for presenting the opportunity to study at Brunel