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1.
Talanta ; 44(7): 1203-9, 1997 Jul.
Article in English | MEDLINE | ID: mdl-18966855

ABSTRACT

A method was developed for the recovery and determination of cyanide ion in organic sample matrices. To facilitate the solubilization of cyanide ions, cetyltrimethylammonium bromide (CTAB) was added at concentrations above the critical micelle concentration. Sample cyanation reaction products consisted of solvent mixtures of a hydroxynitrile in DMF-toluene or DMF-isopropylacetate (IPAC). Spectrophotometric determination of cyanide ion at 578 nm by the pyridine-barbituric acid method was automated by flow injection analysis. Recovery of cyanide ion from spiked samples was 93.2% in DMF-IPAC solvent matrix and 93.9% in DMF-toluene. Low alkali concentration was observed to favor solubilization of cyanide ion in the micellar solution.

2.
Anal Chem ; 62(5): 452-8, 1990 Mar 01.
Article in English | MEDLINE | ID: mdl-2316869

ABSTRACT

The anaerobic voltammetry of the Mo/Fe enzyme, sulfite oxidase (SO), is described for the mediators cytochrome c, [Ru(NH3)6]3+/2+, TMPD+/0, and [Co(bpy)3]3+/2+. Theory derived for steady-state voltammetric catalysis correctly predicts the observed concentration and scan-rate dependencies of the catalytic waves. The instances for which existing ECcat theories may be applied to two catalytic reactions coupled to an interfacial charge transfer are considered. The biomolecular rate constant for the reaction of [Co(bpy)3]3+ with reduced SO is calculated and determined to be approximately 5 X 10(4) L.mol-1.s-1. The appearance of catalytic prepeaks at low sulfite concentrations is noted and the shape of corresponding i/t curves from chronoamperometry is examined. The analytical implications of the novel time dependence of the catalytic current under these conditions are discussed.


Subject(s)
Cytochrome Reductases/analysis , Anaerobiosis , Electrochemistry , Indicators and Reagents , Sulfite Dehydrogenase
3.
Tijdschr Diergeneeskd ; 105(8): suppl 2:104-14, 1980 Apr 15.
Article in English | MEDLINE | ID: mdl-6246656

ABSTRACT

Cyanide is a potent and rapidly-acting asphyxiant which prevents tissue utilization of oxygen by inhibition of the cellular respiratory enzyme, cytochrome oxidase. Inhalation or ingestion of cyanide produces reactions within a few seconds and death within minutes. Cyanide toxicity of dietary origin has been implicated in acute animal deaths and as major etiologic factors in toxic ataxic neuropathy in man and as a cause of vision failure in humans suffering from tobacco amblyopia and leber's hereditary optic atrophy. Diagnosis of cyanide toxicity may be confirmed by a variety of laboratory procedures, but accurate assay is essential for proper conclusions from analysis of animal tissues several hours after death or from human samples in instances of chronic dietary exposure. Biological detoxification of cyanide is available through several routes, and the application of sodium nitrite with sodium thiosulfate or administration of methylene blue are effective treatment procedure. The environmental availability of cyanide in its various forms necessitates an understanding of its pathophysiology and responsible management of hazardous situations.


Subject(s)
Cyanides/toxicity , Absorption , Animal Husbandry , Animals , Chelating Agents/therapeutic use , Chemical Phenomena , Chemistry , Cyanides/antagonists & inhibitors , Cyanides/metabolism , Cyanides/poisoning , Electron Transport Complex IV/antagonists & inhibitors , Environmental Pollutants , Humans , Hydroxocobalamin/therapeutic use , Hypoxia/chemically induced , Inactivation, Metabolic , Poisoning/diagnosis , Poisoning/drug therapy , Poisoning/physiopathology , Poisoning/veterinary , Postmortem Changes , Sodium Nitrite/therapeutic use , Thiosulfates/therapeutic use
4.
Vet Q ; 2(2): 104-14, 1980 Apr.
Article in English | MEDLINE | ID: mdl-22039904

ABSTRACT

Summary Cyanide is a potent and rapidly-acting asphyxiant which prevents tissue utilization of oxygen by inhibition of the cellular respiratory enzyme, cytochrome oxidase. Inhalation or ingestion of cyanide produces reactions within a few seconds and death within minutes. Cyanide toxicity of dietary origin has been implicated in acute animal deaths and as major etiologic factors in toxic ataxic neuropathy in man and as a cause of vision failure in humans suffering from tobacco amblyopia and leber's hereditary optic atrophy. Diagnosis of cyanide toxicity may be confirmed by a variety of laboratory procedures, but accurate assay is essential for proper conclusions from analysis of animal tissues several hours after death or from human samples in instances of chronic dietary exposure. Biological detoxification of cyanide is available through several routes, and the application of sodium nitrite with sodium thiosulfate or administration of methylene blue are effective treatment procedure. The environmental availability of cyanide in its various forms necessitates an understanding of its pathophysiology and responsible management of hazardous situations.

5.
Toxicology ; 15(1): 43-53, 1979 Dec.
Article in English | MEDLINE | ID: mdl-542959

ABSTRACT

Male rats were used to study the inorganic (ionic) and organic fluoride concentrations in plasma, liver, kidneys and stomach content after oral doses of 0, 2.2, 3.5, 4.0, 5.0 and 7.0 mg sodium monofluoroacetate (SMFA, Compound 1080)/kg body weight. Tissue and plasma ionic fluoride concentrations were observed to be higher in all rats given SMFA as compared to rats in the control group. This observation suggests in vivo defluorination of SMFA. Homogenates of liver obtained from SMFA poisoned rats showed significant increases in ionic fluoride concentration during a 6-day storage period at +4 degrees C, with the total fluoride concentration (ionic and organic) remaining constant. The average percentages of distribution of SMFA (organic fluoride) in plasma, liver, and kidneys were 7.05, 5.07 and 1.68, respectively. Plasma and tissue SMFA concentrations were generally lower than the corresponding stomach fluid SMFA concentrations for all dosage groups. Lethal concentration of SMFA in the liquid stomach content was in the range 84.9--189 micrograms/ml, corresponding to total (ionic and organic) fluoride concentrations in the range of 16.1--36 micrograms/ml.


Subject(s)
Fluoride Poisoning/metabolism , Fluorides/metabolism , Fluoroacetates/toxicity , Rodenticides/metabolism , Animals , Fluoride Poisoning/diagnosis , Fluorides/blood , Fluoroacetates/blood , Fluoroacetates/metabolism , Gastric Juice/analysis , Kidney/metabolism , Lethal Dose 50 , Liver/metabolism , Male , Rats , Seizures/chemically induced , Tissue Distribution
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