Peak area observed less than the trend during HPLC analysis

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Trouble description :

During HPLC analysis, sometimes it happens that there is significantly less area observed as compared to previous trend od peak area.

Investigation: 

During investigation everything was checked i.e.:

Checke Solution dilutions prepared for sample and standard and found Ok.

Checked Column leakage and found no leakage.

On changing the HPLC system, same solutions were used and arwawere checked 

Mobile phase filteration checked and it was found that analyst did not filterd the mobile phase

As unfiltered mobile phase was used,so solvent inlet filter was checked

On inevstigating it was found that they were completely choked.

Action taken : Solvent inlet filter was changed and analysis performed.

Area observed in trend.

CAPA:Solvent filter should be sonicated for 30 mins if any variation is observed during the analyis.




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