John Jonsson

A Convenient Derivatization Method for the Determination of Amphetamine and Related Drugs in Urine

The most commonly abused CNS stimulant in Sweden is amphetamine followed by phenmetrazine. Methamphetamine and phentermine are rarely seen but still of interest. This paper describes a rapid and sensitive method for the analysis of amphetamine, methamphetamine, phentermine, and phenmetrazine in urine using gas chromatography with nitrogen sensitive detection (GC-NPD). The method also qualitatively determines ephedrine and norephedrine. The derivatization was carried out at room temperature with methyl chloroformate to form the corresponding carbamates. Other chloroformate analogues were also tested. Because methyl chloroformate is relatively stable in the presence of water the extraction and derivatization were combined in one step. A concentration step was not necessary to achieve sufficient sensitivity. The recovery was more than 83% for all analytes. The LOQ was 0.05, 0.03, 0.07 and 0.01 (microgram/mL urine) for amphetamine, methamphetamine, phentermine and phenmetrazine respectively. The cut-off was set at 0.2 microgram/mL. The within-day and between-day relative standard deviation (RSD) for amphetamine were 2.2% (n = 9) and 4.7% (n = 5) respectively. There was a good quantitative correlation (r2 = 0.995) between GC-NPD using chloroformate derivatives and gas chromatography-mass spectrometry (GC-MS) using trifluoroacetic anhydride (TFA) as derivatizing agent for the determination of amphetamine in authentic samples.

Hydroxylation of amphetamine to parahydroxyamphetamine by rat liver microsomes.

Rat liver microsomes were shown to hydroxylate d- and l-amphetamine at the para position of the benzene ring. The identity of the product, p-hydroxyamphetamine, was established by the use of three different methods, paper chromatography, radio gas-chromatography and mass-spectral analysis. The hydroxylation reaction was found to be linear with time to 15 min and protein concentration to 2 mg/ml. The reaction followed Michaelis-Menten kinetics only at low substrate concentrations. When the concentration of d-amphetamine exceeded 0·5 M the plot indicated substrate inhibition. According to the Linewaaver-Burk plot the following apparent kinetic data were found: d-amphetamine, Km = 2·

Morphine intake from poppy seed food

× 10−5 M, Vmax = 3·7 moles × 10 min; l-amphetamine. Km = 1·1 × 106 M, Vmax = 2·8 nmoles × mg proteins × 10 min−1.

The p-Hydroxylation of Amphetamine and Phentermine by Rat Liver Microsomes

Morphine was determined in commercially available poppy seed and seed cake as well as in urine from healthy normal human adults 3 and 15 h after ingestion of poppy seed cake. The following morphine concentrations were determined: between 374 ±51 and 9.4 ± 1.0 μmol kg−1 poppy seed of different brands, 290 ± 11 μmol kg−1 poppy seed paste, 1.43 ± 0.07 and 0.53 ± 0.15 μmol litre−1 urine sampled 3 and 15 h, respectively, after ingestion of two cakes and 0.67 ± 0.17 and 0.30 ± 0.06 μmol litre−1 urine sampled 3 and 15 h, respectively, after ingestion of one cake. It is concluded that a positive finding of morphine in the urine from a person suspected of heroin abuse calls on some attention due to possible accidental morphine intake from poppy seed food.

Effects of diethyldithiocarbamate and ethanol on the in vivo metabolism and pharmacokinetics of amphetamine in the rat

1. The products of p-hydroxylation of amphetamine and phentermine by two different preparations of rat liver microsomes were identified and quantitatively determined. At low concentrations (muM) significant proportions of the substrates were metabolized to the p-hydroxy derivatives by an NADPH-dependent system. The enzyme system was inhibited by higher substrate concentrations (mM) and was not induced by either phenobarbital or 3-methylcholanthrene. 2. The properties of this in vitro system are consistent with reports on in vivo studies of this reaction.

Is urine a suitable material for the preliminary screening of drugs in autopsy cases

R E F E R E N C E S J. Pharmac. exp. Ther., 145, 64-70. EBLE, J. N. (1964). FURCHGOTT, R. F. (1972). Editors : Blaschko, H. & Muscholl, E. GOLDBERG, L. I. (1972). Pharmac. Rev., 24, 1-29. MCNAY, J. L. & GOLDBERG, L. I. (1966). MCNAY, J. L., MCDONALD, R. H., JR. & GOLDBERG, L. I. (1963). Pharmacologist, 5, 269. ROSSUM J. M. VAN, (1965). J. Pharm. Pharmac., 17, 202-216. TODA, N., USUI, H., NISHINO, N. & FUJIWARA, M. (1972). J. Pharmac. exp. Ther., 181, 512-521. Handbuch der experimentellen Pharmakologie, Vol. 33, pp. 283-335. Berlin: Springer-Verlag.

Interaction of fenfluramine analogues with the in vivo metabolism of (+)-amphetamine in the rat

This paper reports a survey of drug screening in the urine specimens of 45 autopsy cases whose livers contained medicinal substances. The extractions were carried out by a solid phase/liquid technique and the analyses by thin-layer chromatography. Nine compounds out of 43 actually present in the liver were not detectable in the urine; eight cases with high drug concentrations in the liver and also in the blood would have evaded the intoxication suspicion had the urine been used as the only material for the chemical survey. On the basis of these data we advocate that the preliminary drug screening of medical-examiner cases not be carried out on urine alone.

A Method for the Simultaneous Determination of 5‐Hydroxy‐3‐Indole‐Acetic Acid (5‐HIAA) and 5‐Hydroxytryptamine (5‐HT) in Brain Tissue and Cerebrospinal Fluid

Although this compound is extracted only to a minor extent from hepatocytes into the bile. It was possible to show histologically by freeze-drying techniques that BSP entered the hepatocyte after retrograde injection. The cytoplasm and the nuclear membranes showed a dark-blue colour after being made alkaline giving evidence of BSP within the hepatocytes. On the other hand we were not able to detect any destructive alterations of the liver cells which might have been caused by the retrograde biliary injection of a total of 0.07 ml. These results provide clear evidence that an absorption from the biliary system into the hepatocytes is possible and support the suggestion given in this respect by Clark & others (1971).