The Choice, Use, and Maintenance of HPLC Column

With the development of society and technology, chromatographic analysis theory has also been developing rapidly. HPLC column has now been widely applied in every field of laboratory analysis. HPLC column gathers the function of both detection and separation. With the right choice, use, and maintenance, you can keep good performance of the HPLC column. Otherwise, you will make it scrap fastly.

HPLC is a branch of chromatography, that uses a high-pressure infusion system to make the single or mixed solution and buffer mobile phase pump into the column with the stationary phase. After each component is separated, the solution can flow into the detector in order to be analyzed. Normally, the great diversity and complex matrix of the sample are key reasons to make the HPLC column easily polluted.

The Choice of HPLC Column

a. Stationary Phase:

  • Choose a stationary phase based on the nature of the analytes and their interactions with the column material.
  • Common stationary phases include C18 (reverse phase), C8, normal phase, and specialty phases for specific applications.

b. Particle Size:

  • Consider the particle size of the packing material. Smaller particles provide higher resolution but may result in higher backpressure.

c. Column Dimensions:

  • Select the appropriate column length and diameter based on the analytical requirements, sample size, and desired separation efficiency.

d. Compatibility:

  • Ensure that the selected column material is compatible with the mobile phase and sample solvents to prevent damage or degradation.

e. Column Type:

  • Choose between analytical and preparative columns based on the scale of the separation (analytical for small-scale analysis, preparative for larger sample amounts).

In general, the first thing you have to consider when choosing an HPLC column is the sample’s cleanliness. For most researchers, the most appropriate length of the guard column is 2 cm or 3 cm. The length of the guard column, the more chromatographic packings can be filled. Meanwhile, a longer guard column can reduce pollutants and extend the retention time of samples. You also can choose PAH HPLC Column, C1 HPLC Column, ODS C18 HPLC Column, and other HPLC Columns using.

The Right Use of HPLC Column

1. Add HPLC guard column
2. Filter mobile phase and sample
3. Purify sample
4. Avoid overhigh-column pressure
5. Pay attention to temperature and PH level
6. Correct and timely wash

The maintenance of the HPLC Column

1. Softly and moderately change and handle the column
2. Add one column for each analytical instrument to extend the service life
3. Avoid sudden changes in temperature and pressure causing the mechanical shock
4. In general, do not backflush the HPLC column
5. Do not inject samples of complex matrices directly into the HPLC column
6. Pack the HPLC column with acetonitrile or methanol to preserve it
7. Clean the chromatographic analysis system in time after the use

HPLC’s Plunger Rod and Plunger Piston Sealing Ring

Plunger piston sealing rings are divided into normal phase and reversed phase. The reversed-phase sealing ring is with the color of black and made of graphite. The normal phase sealing ring is orange and made of polyethylene, and it is more suitable to the normal phase solvent. Generally, the liquid chromatograph is equipped with a reversed-phase sealing ring. When a normal phase is applied, the sealing ring should be changed into a normal phase.

HPLC plunger piston sealing ring is covered on the plunger rod and used for isolating the pump from the outside. When working, the ring rubs with the rod frequently, and it will be frayed after a period of time. As a result, the plunger piston sealing ring should be changed regularly to ensure of airtightness of the system.

You should check if there is a scratch on the plunger rod when changing the sealing ring. Because scratches will lead to slight leakage and reduce the service life of the sealing ring.

Saline solution has a great influence on the service life of sealing rings. If the saline solution is used as the mobile phase system, you should pay attention to the wash of the solution channel. Moreover, the saline solution cannot be kept in the pump after HPLC stops working.