The Validation of a Bioanalytical Method for the Determination of Fluconazole in Human Plasma

A sensitive, specific and robust liquid chromatography-mass spectrometry (LC-MS) method for the determination of fluconazole (α-(2,4-difluorophenyl)-α-(1H-1,2,4-triazol-1-ylmethyl)-1H-1,2,4-triazole-1-ethanol) in human plasma has been developed and validated. HPLC-UV detection lacked sensitivity and GC-MS analysis was hindered by excessive injection carry-over. The method was successfully developed and validated over a range of 50 ng.mL^?1 to 4000 ng.mL^?1 using protein precipitation. Deuterated fluconazole (d₅) was synthesised ‘in-house’ and used as the LC-MS internal standard. This method has been successfully used to support a bioequivalence clinical study.