Detection of amfepramone and its metabolite cathinone in human hair: Application to a uthentic cases of amfepramone use.

In recent years, overseas anti-obesity drugs including amfepramone have flowed into China through the internet or personal import by travelers. Amfepramone is controlled in China and is not available as a pharmaceutical product. It is obtainable either through the internet or imported by individuals across the border. The abuse of amfepramone is causing serious health problems. A method for the detection and quantification of amfepramone and its metabolite cathinone in human hair was developed and fully validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Approximately 10 mg of hair was weighed and pulverized with extraction solvent (a mixture of methanol: acetonitrile: 2 mM ammonium formate [pH 5.3] [25:29:46, v/v/v]). The limit of detection (LOD) and the limit of quantitation (LOQ) were 5 and 10 pg/mg, respectively. The method was linear over a concentration range from 10 to 10,000 pg/mg. The accuracy varied from -9.3% to 2.3%, with acceptable intra- and inter-day precision. The validated method was successfully applied to 17 authentic cases. The amfepramone concentrations ranged from 11.7 to 209 pg/mg, with a median of 30.2 pg/mg, and the hair cathinone concentrations ranged from 11.9 to 507 pg/mg, with a median of 54.0 pg/mg. This is the first report of amfepramone concentrations in human hair from amfepramone users. Cathinone can be incorporated into hair after amfepramone use.

Determination of amphetamine-type stimulants in oral fluid by solid-phase microextraction and gas chromatography-mass spectrometry.

A method for the simultaneous identification and quantification of amphetamine (AMP), methamphetamine (MET), fenproporex (FEN), diethylpropion (DIE) and methylphenidate (MPH) in oral fluid collected with Quantisal™ device has been developed and validated. Thereunto, in-matrix propylchloroformate derivatization followed by direct immersion solid-phase microextraction and gas chromatography-mass spectrometry were employed. Deuterium labeled AMP was used as internal standard for all the stimulants and analysis was performed using the selected ion monitoring mode. The detector response was linear for the studied drugs in the concentration range of 2-256 ng mL(-1) (neat oral fluid), except for FEN, whereas the linear range was 4-256 ng mL(-1). The detection limits were 0.5 ng mL(-1) (MET), 1 ng mL(-1) (MPH) and 2 ng mL(-1) (DIE, AMP, FEN), respectively. Accuracy of quality control samples remained within 98.2-111.9% of the target concentrations, while precision has not exceeded 15% of the relative standard deviation. Recoveries with Quantisal™ device ranged from 77.2% to 112.1%. Also, the goodness-of-fit concerning the ordinary least squares model in the statistical inference of data has been tested through residual plotting and ANOVA. The validated method can be easily automated and then used for screening and confirmation of amphetamine-type stimulants in drivers' oral fluid.

[Determination of fenfluramine, diethylpropion and mazindol in slimming foods by gas chromatography-mass spectrometry].

A gas chromatography-mass spectrometry (GC/MS) analytical method for three anorectics drugs, fenfluramine, diethylpropion and mazindol, illegally adulterated in slimming foods has been developed. They can be simultaneously identified and quantified. The samples were extracted with chloroform, and then separated by GC with an HP-5MS GC capillary column. The temperature programming was started at 70 degrees C. The temperature was held at this temperature for 2 min and then increased at 10 degrees C/min to 280 degrees C. The completely separated peaks were identified by MS with a quadrupole mass filter and quantitated in selected ion monitoring mode. Compared with the NIST98 library, the matching qualities of the drugs in foods were all over 90%. The calibration curves of the drugs were excellent with correlation coefficients between 0.9991 and 0.9999, and relative standard deviations between 1.6% and 2.2%. The recoveries were between 96.0% and 102.4%. The results demonstrated that this method is suitable for the identification and quantitation of these anorectics drugs in slimming foods.

Simultaneous determination of amfepramon and its two major metabolites in biological fluids by gas liquid chromatography.

Sensitive and specific procedures based on gas liquid chromatography for the identification, separation and determination of amfepramon (diethylpropion) and its major metabolites ethylaminopropiophenone and diethylnorpseudoephedrine in human plasma, saliva and urine have been described. Acidification of the biological fluid samples has improved the stability of the compounds under conditions of storage.

High-performance liquid chromatographic determination of diethylpropion hydrochloride in tablets: isolation and identification of two decomposition products.

A rapid assay was developed for diethylpropion hydrochloride tablets using high-performance liquid chromatography (HPLC) with UV detection. This technique provided separation of the drug from other UV-absorbing components present as the result of decomposition. A major decomposition product detected by HPLC in extracts of tablets and of the cotton filler from a tablet bottle was collected from the column effluents. This product was subsequently identified as 1-phenyl-1,2-propanedione, a highly volatile compound. A second decomposition product, isolated from decomposed drug by distillation from alkaline solution, was identified as diethylamine, apparently present as the hydrochloride salt, GLC, UV, IR, NMR, and mass spectrometry were used to confirm the identity of the decomposition products. HPLC assay results compared favorably with results of the NF assay; the latter procedure separated the drug from 1-phenyl-1,2-propanedione via liquid-liquid extraction.