Developed as a modification of preparative column chromatography in the past few decades, flash chromatography is an air pressure driven technique to gain the rapid separations of organic compounds in the lab. It is approved as a simple, fast, and economical approach to preparative liquid chromatography for chemical species’ purification.
The flash chromatography system consists of a prepacked plastic cartridge, and the solvent is pumped through the cartridges to achieve separation. You can link the flash column system with the detectors and fraction collectors. And the system can even be automated if you want.
With the full line of different sizes, Hawach always provides you the high purity stationary phased packed flash column. And the column cartridge made from medical grade virgin PP and PE materials and different stationary phases prepacked will help you to meet a variety of compounds analysis of a varies of properties from hydrophilic to hydrophobic, such as polar, semi-polar and non-polar compounds.
Types of Fillers
The fillers of the Hawach flash column comprise Al2O3, polymer matrix, silica gel matrix. Each of them has its own advantages and disadvantages, and the following passage presents a brief introduction to them.
1. Al2O3 matrix:
Advantages: the stability is good, and the PH is 1 ≤ 14.
Disadvantages: chemical modification is difficult.
2. Polymer matrix:
Advantages: the stability is good, and PH is 1 ≤ 13; surface chemical treatment can be carried out to meet the needs of reversed-phase chromatography, ion-exchange chromatography, hydrophobic interaction chromatography, and volume exclusion chromatography
Disadvantages: the pore size structure is complex and the pore size is not uniform, resulting in the column effect is not high enough.
3. Silica gel matrix:
Advantages: The most widely used matrix materials at present; with high mechanical strength and high specific surface area; high efficiency, good reproducibility.
Disadvantages: the PH range of silica gel matrix is 3 ≤ 8, which is easy to dissolve at high or low pH; it has the surface activity which is easy to cause the tail of strong alkaline substance and the silicon hydroxyl group with acid.
Regeneration General Condition
Hawach developed a new method to regenerate the flash column which greatly improves the performance and prolongs the service life of the product. In general, it is difficult to regenerate the chemical bonded stationary phase such as silica gel and ODS. Sometimes, the following methods may be used to improve the correction effect.
Specific Steps
1. Due to impurity particles and other factors, the upper end of the column fixed phase discoloration, column efficiency decreased. At this point, the discoloration can be carefully removed and the new stationary phase can be supplemented.
2. When the column adsorbs unwashed components, the column efficiency will decrease obviously, and the appropriate solvent can be selected for cleaning.
3. For the ion exchange resin column, the ion exchange resin column is washed by 1mo/L NaOH solution, then balanced with 1-2mo/L NaC1 aqueous solution and cleaned by the ultrasonic generator, and good results can usually be obtained.
4. When gradient eluting is used, the column is pressed several times the volume of the initial solvent through the column before reuse, in order to re-establish the initial balance to obtain the regeneration.
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