Gel permeation chromatography clean-up for the determination of gestagens in kidney fat by liquid chromatography-tandem mass spectrometry and validation according to 2002/657/EC.

A specific and sensitive method based on liquid chromatography-tandem mass spectrometry using atmospheric pressure chemical ionization (LC-APCI-MS/MS) has been developed for the determination of gestagens in kidney fat (medroxyprogesterone acetate, megestrol acetate and melengestrol acetate). The procedure involved a clean-up procedure with gel permeation chromatography (GPC). The analytes were analyzed by reversed-phase LC-MS/MS, in positive multiple reaction monitoring (MRM) mode, acquiring two diagnostic product ions from the chosen precursor for the unambiguous confirmation of the gestagens. The method was validated at the validation level of 1.0 ng/g. The accuracy and precision of the method were satisfactory. The decision limits CCalpha ranged from 0.20 to 0.22 ng/g while the detection capabilities CCbeta ranged from 0.33 to 0.38 ng/g. The method proved to be sensitive and reliable and thus renders an appropriate mean for residue analysis studies.