method validation by GC

[Dr. Raman Nanduri]

We initiated Residual solvent method by GC validation. Acetone is one of the solvent. And it is already present in the test sample .. about 1400 ppm. The LOQ established is 50 ppm. How to establish recovery (accuracy) at LOQ....

Regards,

[HPLC chemist]

I would NOT perform a 'spike' and 'recovery' experiment at the LOQ concentration because by definition the %RSD at the LOQ is 10.0%. Thus, if you set the acceptance criteria at 2.0 or 5.0% you will fail gloriously! You are demonstrating that your method is consistent and reliable at your expected concentration level. Thus, I would try 50, 100, and 150% of the expected concentrations as long as they are on the linearity curve.