[Determination of fenfluramine hydrochloride in tablets by gas chromatography with derivatization]

The contents of fenfluramine hydrochloride in tablets were determined by using gas chromatography (GC) with derivatization. Five percent SE-30 was used as stationary liquid(2.1 m x 3.2 mm i.d., glass column), and was detected with flame ionization detector (FID). The oven temperature was set at 125 degrees C, with injector and FID temperature at 160 degrees C. The fenfluramine hydrochloride in the tablets was extracted with ethyl acetate and derivatized with trifluoroacetic anhydride at 40 degrees C for 30 min, and then analyzed by GC. The quantitative determination was performed with mexiletine as the internal standard. The method showed good linearity within the mass concentration range from 0.1 g/L-0.5 g/L(r = 0.9996) and the limit of detection was 8 ng. The average recovery of the samples was (100.2 +/- 2.2)% (n = 6). The precision of the method is satisfactory(RSD = 1.4%). The method developed has been applied to the determination of fenfluramine hydrochloride in tablets.