ExcsepTM SCX/SAX Ion Exchange Columns User Manual

Introduction 

ExcsepTM SCX ion exchange columns are made of ultra-high purity, ultra-high mechanical strength spherical chromatography bare silica gel, prepared by the unique surface modification technology of OneTwo Chromatography Technology. Bonded with sulfonic acid groups, it is suitable for the analysis of cationic compounds.

ExcsepTM SAX ion exchange columns are made of ultra-high purity, ultra-high mechanical strength spherical chromatography bare silica gel, prepared by the unique surface modification technology of Onetwo Chromatography Technology. Bonded quaternary ammonium groups, suitable for the analysis of anionic compounds.

Column Activation

The activation of ExcsepTM SCX, SAX ion exchange chromatography columns requires flushing with 100% water, the flow rate is usually set to 1.0 mL/min, and the column is flushed for at least 5~10 column volumes before switching to the analytical mobile phase. 

Note: The equilibration time of the ion exchange chromatographic column is long, usually takes 1~2 hours.

Column Flushing and Storage

If the mobile phase contains buffer salts or ion-pair reagents, be sure to use the same proportion of aqueous phase for the transition. For example, if the mobile phase used is 20% methanol and 80% phosphate buffer, then before switching to the pure organic reagent, the column needs to be flushed with 20% methanol and 80% water for at least 5~10 column volumes, or else there may be a problem with buffer salt precipitation due to the incompatibility of the buffer salt system with the pure organic phase.

ExcsepTM SCX, SAX ion exchange columns are recommended to be stored in pure organic solvents for long-term storage; for short-term storage, it is recommended to be stored in pH 3-7 buffer (e.g., 20 mM phosphate) or mobile phase.

The mobile phase range for ExcsepTM SCX, SAX ion exchange columns is shown in the table below:

Solution for Column Efficiency Reduction

When the chromatographic column shows abnormal phenomena such as increased column pressure, decreased column efficiency, abnormal peak shape, and decreased separation, it is necessary to maintain the column: