Related Experiment Video
Updated: May 13, 2026

On-chip Isotachophoresis for Separation of Ions and Purification of Nucleic Acids
Published on: March 2, 2012
ORGANIC-HIGH IONIC STRENGTH AQUEOUS SOLVENT SYSTEMS FOR SPIRAL COUNTER-CURRENT CHROMATOGRAPHY: GRAPHIC OPTIMIZATION
1Bioseparation Technology Laboraotry, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, 10 Center Drive, Bldg. 10, Rm 8N230, DhBethesda, M.D., USA ; Institute of Materia Medica and Department of Pharmacology, North Sichuan Medical College, Nanchong, 63007, Sichuan Province, China.
Abstract:
A new series of organic-high ionic strength aqueous two-phase solvents systems was designed for separation of highly polar compounds by spiral high-speed counter-current chromatography. A total of 21 solvent systems composed of 1-butanol-ethanol-saturated ammonium sulfate-water at various volume ratios are arranged according to an increasing order of polarity. Selection of the two-phase solvent system for a single compound or a multiple sample mixture can be achieved by two steps of partition coefficient measurements using a graphic method. The capability of the method is demonstrated by optimization of partition coefficient for seven highly polar samples including tartrazine (K=0.77), tryptophan (K=1.00), methyl green (K= 0.93), tyrosine (0.81), metanephrine (K=0.89), tyramine (K=0.98), and normetanephrine (K=0.96). Three sulfonic acid components in D&C Green No. 8 were successfully separated by HSCCC using the graphic selection of the two-phase solvent system.
Related Concept Videos
High-Performance Liquid Chromatography: Elution Process
High-Performance Liquid Chromatography: Introduction
In HPLC, two phases play a critical role in the separation process:
Ion-Exchange Chromatography
Optimizing Chromatographic Separations
Band broadening refers to spreading solute bands as they travel through the column. This broadening can impact resolution. Plate height (H) represents the length required for one theoretical plate. A lower plate height corresponds to...
Supercritical Fluid Chromatography
SFC utilizes a supercritical fluid mobile phase,...
High-Performance Liquid Chromatography: Instrumentation

