Peak Tailing Diagnosis and Solutions

Acceptable levels of peak tailing should be indicated in the system suitability section of the method as peak asymmetry or tailing factor. Once the limits have been exceeded, a number of basic checks can be carried out that can assist in the diagnosis. A lot of problems of this nature are found to be due to analyst error, and the mobile phase composition and column choice should always be checked as a matter of course. 

Note In the case of an incorrect column, the wrong one should be washed out thoroughly with an appropriate solvent before storage. 

If either the column or the mobile phase is incorrect, then this should be put right immediately and the system allowed to reequilibrate under the correct operating conditions before repeating the analysis. 

Note Before repeating any analysis, always consult with your supervisor or line manager and ensure that you are following the correct procedure and protocol for such eventualities. 

The column should be reassembled and reattached to the HPLC system. It should be allowed to reequiUbrate and an injection should be performed. The peak shape should be assessed and, if an improvement is apparent and the system suitability criteria are met, the column can be used for the analysis. Quite often it is necessary to repeat the slurry application several times in order to fill the void completely. This can be time consuming and in some instances the preferred option is to replace the column. 

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