The filling of liquid chromatography columns, especially high performance liquid chromatography columns, requires high skill and skill. Therefore, some people even regard “packing†as “art plus technologyâ€. However, as long as you master some basic rules and methods, any laboratory can fill columns with higher column performance. Of course, most laboratories currently purchase pre-packed columns for commodity separation and analysis. However, in some cases with special needs, or to save money, it is advisable to fill the HPLC column in the laboratory.
Issues to be aware of in the liquid chromatography column packing procedure:
1 Safety issues with high pressure operation. A common problem is that the column is not firmly connected to the homogenization tank, causing the column head to be washed down by high pressure or the column to slip off the homogenization tank when pressurized. At this time, if the filling fails, the material is lost, and the personal injury is caused by the damage. It must be prevented. In addition to carefully checking whether the connection is correct and secure before each filling, it is best to add a preventive device consisting of a flange and a long screw, just in case.
2 Usually, the column bed that is first filled is tighter than the post bed that is filled later. Therefore, it is preferred to use the opposite direction when using, that is, one end of the near homogenization tank is used as the outlet of the mobile phase at the time of use, and the outlet end at the time of filling is used as the inlet of the mobile phase.
3 The new column should be rinsed with methanol for 20-30 minutes before use, and then switched to mobile phase equilibrium.
4 New columns should be selected and evaluated for appropriate standard samples for review and comparison.
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