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A simple method to optimize the HSCCC two-phase solvent system by predicting the partition coefficient for target

Quan-Bin Han¹, Lina Wong, Nian-Yun Yang

¹Chinese Medicine Laboratory, Hong Kong Jockey Club Institute of Chinese Medicine, Hong Kong, China.

Journal of Separation Science

|February 29, 2008

Summary

A new method optimizes solvent ratios for high-speed counter-current chromatography (HSCCC) separations. This approach successfully isolated pseudolaric acid B from a Chinese herb with high purity.

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Area of Science:

Chromatography
Natural Product Chemistry

Background:

High-speed counter-current chromatography (HSCCC) is a liquid-liquid separation technique.
Optimizing the two-phase solvent system is crucial for efficient HSCCC separation.

Purpose of the Study:

To develop a simple and effective method for optimizing the solvent ratio in HSCCC.
To apply this method for the preparative isolation of pseudolaric acid B.

Main Methods:

Mathematical equations (exponential and power) were derived to correlate solvent ratio and partition coefficient.
The optimized solvent system was determined using these equations.
HSCCC was employed for the separation and purification of pseudolaric acid B.

Main Results:

A novel method for optimizing HSCCC solvent systems was successfully developed.
The optimal two-phase solvent system (n-hexane/EtOAc/MeOH/H2O, 5:5:5:5 v/v) yielded a partition coefficient (K) of 1.08.
232.05 mg of pseudolaric acid B was obtained from 0.5 g of crude extract with 97.26% purity.

Conclusions:

The developed method provides an efficient way to determine optimal solvent systems for HSCCC.
This method facilitates the successful preparative isolation of valuable compounds like pseudolaric acid B.