Description of HPLC SAX Strong Anion Exchange Columns
Storage solution in the chromatography column: 100% methanol
The aperture of the sieve plate at both ends of the chromatography column is 2μm, and the column can be back flushed
SAX column usage characteristics
1) Commonly used to separate compounds that are anionic in aqueous solution;
2) The SAX HPLC column is compatible with water and organic solvents, and methanol, acetonitrile, and water (including buffer salt solutions) can be used as mobile phases for analysis;
3) The retention capacity of anionic compounds is related to the pH, ionic strength of the mobile phase, the ratio of the organic phase in the mobile phase, and the temperature. Generally, the greater the ionic strength, the shorter the retention time, and the greater the proportion of organic phase in the mobile phase, the longer the retention time;
4) Buffer salts such as citrate and phosphate are usually used to adjust the pH and ionic strength of the mobile phase to improve the resolution, but should not exceed its pH range;
5) The equilibrium time of the anion exchange column is longer than that of C18.
Features of SAX HPLC Columns
Adopt highly controllable polymerization monolayer formation and tail sealing technology
Mixed chemical structure containing a quaternary ammonium group and phenyl functional group
It has dual functions of ion exchange and hydrophobic effect, so it has high selectivity and suitable retention for many compounds
Due to the use of polymer chemical bonding and tail sealing technology, it has excellent stability
Suitable for separating various organic compounds such as aromatic or aliphatic carboxylic acid and sulfonic acid, etc.
Maintenance of SAX Columns
1) The mobile phase is suction filtered through a 0.45μm filter membrane, and the sample syringe is filtered;
2) Before use, first, use the transition mobile phase to transition for 30 minutes at 1.0ml/min, then use the mobile phase to take the baseline, and then inject the sample after the baseline is stable; after use, first, flush the column with pure water at 1.0ml/min for 40 minutes; Then backwash with 40% methanol for 40 minutes and save; the transitional mobile phase refers to the organic phase and water phase ratio is the same as the mobile phase, but the transitional mobile phase does not contain buffer salts;
3) Use guard columns and pre-columns to extend the service life of chromatography columns;
4) Regeneration: connect the column in the opposite direction, flow rate 0.4ml/min, and elute 30ml respectively, and then 1M ammonium nitrate—40% methanol solution—isopropanol—water—eluent, and then pack the column in the specified direction. The eluate eluted to equilibrium.
Storage of SAX HPLC Columns
Store in 40% pure methanol (or acetonitrile). Before storing in 40% pure methanol (or acetonitrile), make sure that the column does not contain buffer salts;
Short-term storage (one or two days):
Store in a transitional mobile phase with the same ratio as the mobile phase but without buffer salts.