Performance, Preparation, Usage, and Operation of Flash Column

Being a rapid way to separate the lighter components from the heavier ones in the complex mixtures of compounds, the flash column is a vassal smaller in scale and easy to use. The principles of column chromatography are the same as in the TLC. When we run the flash columns, the compressed air will be pushed the solvent through the flash column. When can help you get a better separation, and save a lot of running time for your application?

Flash chromatography is performed with silica gel in the flash column, and in recent years, reversed-phase packing is being used more commonly. To meet the need of different compounds, Hawach is always ready to provide you the empty flash columns which are also called solid load cartridges. Available in sizes from 4 grams to 330 grams, the Hawach flash column is made of medical-grade PP material with standard Luer lock connection fittings.

Perfect for the application of insoluble sample purification, Hawach flash columns can be reused between batches and can be compatible with all normal and reversed-phase solvents. the Hawach empty flash column also can be used for both acidic and basic compounds. Neutral alumina flash columns are widely used in pharmaceutical companies and laboratories. The spherical SAX flash columns can especially retain acidic compounds. The packing tool is available too.

Performance of Flash Column

Before the column is used, it is best to test the performance of the flash column and save the results as a reference for evaluating the change of column performance in the future. However, it should be noted that the flash column performance may vary according to the different conditions of the sample, mobile phase, column temperature, etc.
empty flash column chromatography cn flash column chromatography

In addition, the column performance test is carried out according to the conditions in the chromatographic column factory report and the conditions used in the factory test are the best conditions, only in this way, the measured results are comparable.

Preparation of Flash Column

Flash column is often used to separate complex mixtures of compounds. In order to save time required to operate a flash column, and provide better separation, Hawach uses compressed air to push solvent through the flash column and adopts advanced technology to reduce the risk for operation.

It is significant to pick the appropriate size of flash columns because it can determine the separation performance. Once you have selected a flash column, you had better plug the stopcock end to avoid the silica draining out. This can be done with a small piece of cotton or a long glass rod.

Usage of Flash Column

  1. Choosing the Stationary Phase:
    • Select a suitable stationary phase material based on the properties of the compounds to be separated. Common materials include silica gel or reversed-phase materials.
  2. Packing the Column:
    • Pack the column with the chosen stationary phase material. It’s important to ensure an even and consistent packing to achieve efficient separation.
  3. Equilibration:
    • Prior to sample loading, equilibrate the column with the mobile phase. This involves passing the solvent through the column to wet the stationary phase and ensure consistent conditions.
  4. Sample Loading:
    • Load the sample onto the column through the sample loading port. The sample is often dissolved in a small volume of solvent that is compatible with the mobile phase.
  5. Elution:
    • Elute the compounds by passing a solvent or a solvent mixture through the column. The choice of the mobile phase and its gradient is crucial for separating the components based on their polarity and other properties.
  6. Fraction Collection:
    • Collect the eluted fractions in tubes or containers. Fraction collection is typically based on the elution profile observed during the chromatography process.
  7. Monitoring the Process:
    • Monitor the elution process using techniques such as UV detection or other detectors depending on the nature of the compounds. Adjust the elution conditions if needed.
  8. Analysis of Fractions:
    • Analyze the collected fractions using appropriate analytical techniques to identify the presence of the desired compounds and assess the purity of the fractions.
  9. Post-Column Cleanup (Optional):
    • If needed, additional purification steps or cleanup procedures can be applied to further refine the isolated compounds.
  10. Cleaning and Storage:
    • After completing the separation, clean the column by flushing with an appropriate solvent. Store the column properly for future use.

Fill the column with eluent: when adding solvent to flash columns, the stopcock should be opened. The solvent should be added by pipet until the solvent is above the column. Once the column is filled with eluent, adjust air pressure to quicken the flow rate and help to give good separation. If you want to decrease air pressure, you should monitor the column progress gradually. When the column is drying, it is better to start to combine fractions and make the air push all remaining solvents out of the flash column.

Operation of Flash Column

1. Sample pretreatment:

a. It is ideal to use the mobile phase to dissolve the sample.
b. Use a pretreatment column to remove strong polarity in the sample or produce irreversible adsorption impurities with the column filler.
c. Use a 0.45µm filter membrane to remove particulate impurities.

2. Formulation of mobile phase: liquid chromatography is the separation of sample components by the mass exchange between column packing and mobile phase, so the mobile phase is required to have the following characteristics: flow has a certain solubility relative to the sample, ensuring that the sample components do not precipitate in the column (or remain in the column for a long time).