Determination of dextromoramide by capillary gas chromatography and electron impact mass spectrometry.

A sensitive and specific quantitative assay for the determination of dextromoramide in human fluids and tissues is described. Dextromoramide and an internal standard, SKF 525 A, are isolated by a basic extraction and back-extraction process. The final extract is separated on a 25-m capillary column B.P. 1 and drugs are detected by selected ion monitoring at m/z 100 and m/z 86 for dextromoramide and the internal standard, respectively. The minimum detectable quantities are 0.5 and 0.3 ng/mL, for dextromoramide in plasma and urine, respectively. Coefficients of variation for within-run data were less than 6%.

Simultaneous determination of dextropropoxyphene, norpropoxyphene and methaqualone in plasma by gas chromatography with selective nitrogen detection.

A method for the identification and quantification of dextropropoxyphene, norpropoxyphene, and methaqualone in plasma by GC/NPD is presented. The procedure employs cyclizine as the internal standard and requires no derivatization. After a single-step extraction, analysis is achieved in 8 min. The lower limits of detection were found to be 6, 12, and 1 ng/ml for dextropropoxyphene, norpropoxyphene, and methaqualone, respectively. This method appears to be rapid, sensitive, and applicable to forensic and clinical toxicological analyses.

A rapid and sensitive gas chromatographic analysis of methadone and its primary metabolite.

A method for identification and quantification of methadone and its primary metabolite (1,5-dimethyl-3,3-diphenyl-2-2-ethylidene pyrrolidine) in plasma by GC/NPD is presented. The procedure employs SKF 525 A as the internal standard and requires no derivatization. After a single-step extraction, analysis is achieved in 10 min. The limit of detection was found to be 2 an 3 ng/ml for methadone and its metabolite, respectively. This method appears to be rapid, sensitive and applicable to forensic and clinical toxicological analyses.

Simultaneous determination of pethidine (meperidine), phenoperidine, and norpethidine (normeperidine), their common metabolite, by gas chromatography with selective nitrogen detection.

This article describes a selective gas chromatographic method for the resolution and quantification of phenoperidine and its two metabolites, pethidine (meperidine) and norpethidine (normeperidine). Drugs and SKF 525 A, the internal standard, are separated from plasma by solvent extraction under alkaline conditions. They are chromatographed on a 3% OV-17 Chromosorb Q glass column and detected with a nitrogen-phosphorous detector. Linearity is observed in the study range (5-200 ng/ml). No interference by endogenous substances is noted.

A simple gas chromatographic identification and determination of 11 CNS stimulants in biological samples. Application on a fatality involving phendimetrazine.

A method is presented for the simultaneous identification and quantification of several CNS stimulants, including amphetamine in plasma and urine by GC/FID using mephentermine as an internal standard. No derivation is necessary and after a single alkaline extraction, GC analysis for the 11 compounds tested is achieved in 23 min. The lower limit of detectability was found to be 4 ng/ml for amphetamine in plasma. This method is sensitive, reproducible, selective and applicable in forensic and clinical toxicological analyses. Toxicological findings, after a fatality involving phendimetrazine are presented as an application of the procedure.

Identification by GC/MS of 6-monoacetylmorphine as an indicator of heroin abuse.

A capillary gas chromatography mass spectrometry assay has been developed for the determination of 6-monoacetylmorphine in human urine, which is a confirmatory marker of heroin abuse. It was extracted with chloroform-isopropanol-n-heptane (50:17:33, v/v) from alkalinized samples (pH 9.2), using levallorphan as the internal standard. After derivatization with trifluoroacetic anhydride, the drugs were separated on a 25-m capillary column BP 10 and detected by selected ion monitoring.

Simultaneous identification and quantification of several opiates and derivatives by capillary gas chromatography and nitrogen selective detection.

A capillary column gas chromatographic method is described for the simultaneous determination of morphine, codeine, heroin, 3- and 6-monoacetylmorphine, nalorphine, naloxone, ethylmorphine, and naltrexone. The drugs were extracted from 2 ml plasma, urine, or other biological samples, including tissue under alkaline conditions in chloroform-isopropanol-n-heptane (50:17:33, v/v), with levallorphan as an internal standard. The drugs were extracted into acid and then reextracted into chloroform after the acid had been alkalinized. After derivatization with trifluoroacetic anhydride, an aliquot was injected into a 25m capillary column equipped with a nitrogen phosphorus detector. The lower limits of detectability, extraction recovery, and the within-run and day-to-day precision of results were determined for each drug. Our results indicate that the procedure is suitable for use in overdose screening and therapeutic drug monitoring.

Identification and quantification of trihexyphenidyl and its hydroxylated metabolite by gas chromatography with nitrogen-phosphorus detection.

A sensitive and specific assay for the simultaneous quantification of trihexyphenidyl and its hydroxylated metabolite in plasma and urine is described. The method is based on the extraction of the drugs with an organic solvent and separation on a 3% OV-17 Chromosorb Q column in a gas chromatograph equipped with a nitrogen-phosphorus detector. The procedure employs SKF 525 A as the internal standard and requires no derivatization. The detection limit was found to be 2 ng/mL for trihexyphenidyl and 1 ng/mL for its metabolite. The precision of the assay procedure for both compounds is about 4 to 7%.

A rapid and sensitive gas chromatographic analysis of meprobamate or carisoprodol in urine and plasma.

A method for the identification and quantification of meprobamate or carisoprodol in plasma by GC/FID is presented. The method employs vinylbarbital as the internal standard and requires no derivatization. After a single extraction, analysis is achieved in 7 min. This method is thus rapid, sensitive, reproducible, selective, and applicable to forensic and clinical toxicological analyses.

Morphological alterations induced by patulin on cultured hepatoma cells.

Patulin is a mycotoxin produced by various Penicillium, Aspergillus and Byssochlamys species. To evaluate its inhibitory effect on cells, hepatoma tissue culture cells in suspension were incubated in presence of 30 microM of patulin for 7 h and investigated by transmission and scanning electron microscopy. By transmission electron microscopy, the most significant difference observed between treated and control cells was the disorganization of the cytoplasmic microfilaments in the treated cells. The disappearance of superficial membrane microvilli which contain microfibrillar material was visualized by scanning electron microscopy; the cells also presented protrusions. The effect of this toxin on the cytoskeleton can be compared to that exerted by colchicine or by cytochalasins.

Action on ricin and its polypeptide chains on cultured hepatoma cells.

The effect of ricin, the glycoproteic toxin from castor beans, as well as of its two polypeptide chains A and B, was studied on hepatoma tissue cell suspension cultures (HCT). The isolated A and B chains have no action. Ricin at a 0.3 microgram/ml concentration, for 3 x 10(5) cells/ml, has a cytostatic effect which becomes cytotoxic after 72 h. This effect exists even if the cells are preincubated for 4 with ricin and washed afterwards. The protein content of the ricin-treated cells decreases. Protein synthesis measured by the incorporation of [3H]-leucine in the cell proteins begins to be inhibited after 30 min and is completely blocked after 2 h for a ricin concentration of 0.3 microgram/ml. DNA synthesis is inhibited from 1 h on. Finally the level of the DNA slows down from 3 h on, whereas the level of RNA abruptly falls between 4 and 5 h. The inhibitory effects are likely to be a consequence of protein synthesis inhibition, but a direct effect on the nucleic acids is not excluded.

[Ricin, the toxic protein of the castor-oil plant (Ricinus communis L). Structure and properties (author's transl)]. / La ricine, protéine toxique du ricin (Ricinus communis L.). Structure et properiétés.

Ricin is an extremely toxic phytotoxin from the castor-oil plant seeds. This toxin is different from the two phyto-hemagglutinins or lectins which are also present in the seeds and can be purified in two chromatographic steps. Studies on the physical and chemical properties of pure ricin are given (molecular weight: 65 750 daltons, glycoproteic nature, oses composition: 15 moles of mannose and 8 moles of N-acetyl-glucosamine per mole of ricin, aminoacids composition: 545, bicatenary structure: the toxin is formed by two polypeptide A and B chains linked together by a disulfure bond). Though ricin is resistant to proteolytic enzymes under normal conditions, we have found conditions in which tryptic hydrolysis of the toxin gives several peptides which retain toxicity. Two of them were purified. The LD50 on mice of ricin and its isolated toxic peptides were determined, the symptoms of ricin's intoxication were established on animals which died from a dramatic hepatonephritic injury, but always after a lag. Ricin has a cytostatic, and then a cytotoxic effect on cells in culture which are highly damaged (important membranous protrusions). The mechanism of ricin's action was studied. It inhibits elongation in protein synthesis in vivo as well as in vitro, by acting on ribosomes whether cytoplasmic, mitochondrial or chloroplastic. To act, the ricin A-chain must be activated by ribosomes which split the ricin molecule into its polypeptide chains; these ribosomes are then frozen by the toxin and became inefficients in protein synthesis.