Highly sensitive and specific determination of mefloquine in biological fluids using gas chromatography mass spectrometry with selected ion monitoring.

A highly sensitive and specific assay for the determination of racemic erythro-alpha-(2-piperidyl)-2,8-bis(trifluoro-methyl)-4-quinoline-methanol in whole blood, plasma and urine has been developed. The method involves the extraction of the drug together with an internal standard, formation of the corresponding O-trimethylsilyl-N-trifluoroacetyl derivatives, gas chromatographic separation and mass spectrometric measurement of the peaks by selected ion monitoring. The method has a sensitivity of 1 ng ml-1 for plasma and 3 ng ml-1 for whole blood or urine. It has been applied to the analysis of mefloquine in plasma following an oral dose of 250 mg of the drug to healthy subjects. No interference was observed from the simultaneous administration of Fansidar.