Determination of amantadine in human plasma by capillary gas chromatography using electron-capture detection following derivatization with pentafluorobenzoyl chloride.

A specific, sensitive, and accurate capillary gas chromatographic method for the quantitation of amantadine in human plasma is described. Amantadine and the internal standard, rimantadine were extracted from plasma under alkaline conditions into toluene. Both compounds were derivatized with pentafluorobenzoyl chloride. The derivatives were separated on a HP-1 capillary column at 180 degrees C and detected using a 63Ni electron-capture detector. The minimum quantifiable limit of the assay is 2.3 ng ml-1 of amantadine base using 1 ml of plasma. The method was used to evaluate the bioequivalence of two different formulations of amantadine hydrochloride.