Fillers of Flash Column

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 with a high-purity stationary phased-packed flash column. Such as Spherical SCX Flash Column, Spherical C8 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 various 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, and silica gel matrix. Each of them has its own advantages and disadvantages, and the following passage presents a brief introduction to them.

1. Silica Gel:

  • Description: Silica gel is a popular and versatile filler for flash columns. It is available in various particle sizes and can be functionalized for specific applications.
  • Applications: Silica gel is suitable for a wide range of compounds and is commonly used for general flash chromatography.

2. Alumina:

  • Description: Alumina is another widely used filler with excellent separation capabilities. It is available in acidic, basic, and neutral forms.
  • Applications: Alumina is often chosen for compounds that do not separate well on silica gel or for specific types of reactions.

3. Florisil:

  • Description: Florisil is a magnesium silicate-based material known for its adsorption and separation properties.
  • Applications: Florisil is commonly used for the separation of polar compounds, such as pesticides and some natural products.

4. Reverse-Phase Silica:

  • Description: Reverse-phase silica is modified with hydrophobic groups, making it suitable for the separation of non-polar and moderately polar compounds.
  • Applications: Reverse-phase silica is used when normal-phase columns do not provide sufficient separation, especially for lipophilic compounds.

5. C18 Silica:

  • Description: C18 silica is a type of reverse-phase silica with a hydrophobic octadecyl (C18) chain attached to the silica surface.
  • Applications: C18 silica is commonly used for the separation of non-polar compounds in reversed-phase flash chromatography.

6. Ion-Exchange Resins:

  • Description: Ion-exchange resins are used for the separation of charged compounds based on their ionic interactions.
  • Applications: Ion-exchange resins are chosen when separation by charge is critical, especially for ionic or polar compounds.

7. Size-Exclusion Resins:

  • Description: Size-exclusion resins are used to separate compounds based on their molecular size.
  • Applications: Size-exclusion resins are suitable for the separation of large biomolecules or polymers.

8. Normal-Phase Silica:

  • Description: Normal-phase silica is the standard silica gel used in flash columns for the separation of a wide range of compounds.
  • Applications: Normal-phase silica is versatile and is suitable for most flash chromatography applications.

9. Diol Silica:

  • Description: Diol silica is modified with diol functional groups, providing unique selectivity for certain polar compounds.
  • Applications: Diol silica is chosen for the separation of polar compounds, including sugars and some natural products.

10. Al2O3 matrix

Advantages: the stability is good, and the PH is 1 ≤ 14.

Disadvantages: chemical modification is difficult.

11. 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.

Standard Chromatographic Silica Gel Flash Columns.png
Spherical Phenyl Flash Columns suppliers

12. Silica gel matrix

Advantages: The most widely used matrix materials at present; with high mechanical strength and high specific surface area; high efficiency, and good reproducibility.

Disadvantages: the PH range of the silica gel matrix is 3 ≤ 8, which is easy to dissolve at high or low pH; it has a 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 chemically 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, and 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 with 1mo/L NaOH solution, then balanced with 1-2mo/L NaCl 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.