Simple and simultaneous analysis of fenfluramine, amphetamine and methamphetamine in whole blood by gas chromatography-mass spectrometry after headspace-solid phase microextraction and derivatization

A simple and sensitive method for the simultaneous analysis of fenfluramine, amphetamine and methamphetamine in whole blood was developed using a headspace-solid phase microextraction (SPME) and derivatization. A 0.5 g whole blood sample, 5 microl d(5)-methamphetamine (50 micrig/ml) as an internal standard, and 0.5 ml sodium hydroxide (1 M) were placed into a 12 ml vial, and sealed rapidly with a silicone septum and an aluminum cap. Immediately after the vial was heated to 70 degrees C in an aluminium block heater, the needle of the SPME device was inserted through the septum of the vial, and the extraction fiber was exposed in the headspace for 15 min. First, heptafluorobutyric anhydride was injected into the injection port of the GC-MS, and the compounds extracted by the fiber were then desorbed and derivatized simultaneously by exposing the fiber in the injection port. The calibration curves, using an internal standard method, demonstrated good linearity throughout the concentration range from 0.01 to 1.0 microg/g. The detection limits of this method were 5.0 ng/g for fenfluramine and methamphetamine, and 10 ng/g for amphetamine. No interferences were found, and the time for analysis was about 30 min for one sample. This method was applied to a suicide case in which the victim ingested fenfluramine. Fenfluramine was detected in the blood sample collected from the victim at the concentration of 7.7 microg/g.