Depending on the analytes you use the Column with, there are a number of Strategies you can try:
- If your HPLC System can have more than two Solvents, you could include a Third Line with a Cleaning Solvent. Then in the Injection Sequence you could insert a Wash Step which uses only the Third solvent. The nature of the samples will dictate how frequently you need to do a washing. For Serum Samples, we recommend about every Ten Injections or Fewer.
- Using a Guard Column can be an effective Technique because strongly adsorbed contaminants will build up at the front of the Column. Therefore if you have a Guard Column attached, these Compounds will build up here instead of on the analytical Column. You can then replace these Guard Cartridges as needed.
- You can also Backflush the Analytical Column. If the Column is facing the other direction, the contaminants will come off more easily.
The advantage of using Cogent™ TYPE-C Columns over those based on ordinary Type B Silica Columns is that they can be more readily cleaned and restored to initial conditions. The reason is because of surface differences between the two materials where Cogent TYPE-C™ Columns are more hydrophobic and has virtually no silanols. Contaminants can therefore be more readily washed from the column. In contrast, contaminants may be more strongly adsorbed onto Type B Columns due to the more active Surface sites on this material.