GC066 Special Troubleshooting Considerations for Capillary Columns – Column bleed

 Column bleed usually occurs when columns are temperature programmed near the maximum permitted column temperature. It is the process of evaporation or thermal decompose of the stationary phase. Column bleed can be seen as an increase in the baseline as the column is heated and it becomes constant when it is held constant. The effect can become more pronounced as the column ages. Column bleed can be diminished by using thinner films, or by selecting a stationary phase with greater temperature resistance or that whose interactions with the analytes is smaller.

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