During the use of the chromatographic column, there will be high column pressure and poor peak shape. The main reason is the contamination of the chromatographic column packing. The following will analyze the causes and solutions for the contamination of the chromatographic column packing.
Analysis of the causes of packing pollution
1. Traditional Chinese medicine samples have complex components. If the pretreatment is too simple, it is easy to cause strong retention components to accumulate at the inlet end of the chromatographic column, resulting in increased column pressure, decreased column efficiency, abnormal peak shape, or appeared in the chromatogram. “Ghost Peak”.
2. Accumulation of protein samples: biological samples are easy to accumulate at the head end of the column, resulting in increased column pressure and decreased column efficiency.
3. Others: samples such as gelatinous and flocculent samples cannot be removed by filtration, and will also accumulate on the frit and column head end, causing the column pressure to rise.
Samples with complex components such as traditional Chinese medicine
1. During method development, try to use SPE cartridges, extraction and other methods to remove as many impurities as possible.
2. When using the guard column, it should be noted that the core of the guard column is a consumable material and cannot be used for a long time without replacement. Once the protection capacity of the column core is exceeded, the strongly retained substances will still enter the chromatographic column. If the pressure increases by more than 10%, it is recommended to replace the cartridge.
3. For the column to detect the complex components of traditional Chinese medicine, it is recommended to regularly perform column maintenance according to the abnormal regeneration method in the column manual. Strongly retained material at the head end of the column.
4. If the chromatographic column of this type of product is overpressured or the column efficiency does not meet the requirements, it is recommended that the customer first deal with the abnormal regeneration method in the manual. If it still cannot be solved, apply for maintenance according to the relevant regulations of the company.
Protein sample accumulation
1. Use more effective pretreatment methods such as SPE.
2. Periodic column maintenance flushes are recommended to remove protein solvents (acetonitrile-water-trifluoroacetic acid = 50-50-0.1).
3. Use a guard column.
4. For these reasons, once the column pressure increases and the column efficiency decreases, the possibility of recovery after maintenance is very small. Therefore, it is recommended that customers perform regular maintenance and add guard columns during use.
Such as gelatinous, flocculent and other samples cannot be removed by filtration, and will also accumulate on the frit and column head end, causing the column pressure to rise. In this category, it is best to solve it in sample processing or process.