Estimation of Microquantities of Cyanide

Abstract

A method is described for the estimation of microquantities of cyanide (or thiocyanate) ion. As little as 0.2 microgram of cyanide can be estimated with an accuracy of 99 * 4% standard deviation.Larger amounts of cyanide may be recovered with less deviation. ALTHOUGH many methods have been reported for the l microestimation of cyanides, few are both sensitive and reliable. The methods of estimation based upon the reaction of cyanides with picric acid (8) and the formation of Prussian blue (7) are comparatively insensitive. Good sensitivity has been acquired with the phenolphthalein %), o-cresolphthalein (8), and Aldridge (1) methods. The method described herein has the sensitivity of any of these, and in addition has the distinct advantage that it may be carried out in acid, neutral, or slightly alkaline media.Gehauf eí al. (£) used a pyridine-pyrazolone mixture for the detection of cyanogen halides. In this method, cyanogen chloride or bromide reacts with pyridine to form glutaconic aldehyde which forms a blue colored dye with 1 -phenyl,3-methyl, 5-pyrazolone.

Effect of passive smoking on thyroid function in infants

“…Thiocyanate was assayed with standard colorimetric methods available for the determination of small amounts of thiocyanate in biological fluids, based on the method developed by Aldridge (9) and Epstein (10) and modified by Jimenez et al (11). The method was based on the chemical reaction of thiocyanate with Fe(NO 3 ) 3 reagent, producing a coloured complex.…”

Novel Sensitive Spectrophotometric Method for the Trace Determination of Cyanide in Industrial Effluent

“…5 In wastewater, the total cyanide, which includes both complexed and uncomplexed forms of cyanide, is analyzed by the standard distillation method. 4 Spectrophotometric methods [6][7][8] for the determination of cyanide are far more superior to the other methods, such as titrimetric, 9 polarographic, 10 fluorometric 11 and chromatographic techniques. 12 A trace amount of cyanide is often determined by spectrophotometry by the pyridine-benzidine method of Aldridge, 6 the pyridine-pyrazolone method of Epstein, 7 the pyridine-barbituric acid method of Asmus and Garschagen 13 and the pyridine-p-phenylenediamine method of Bark and Higson.…”

Mutagen from the Gaseous Phase of Protein Pyrolyzate

“…The HeN. The HCN contents of the gaseous phase of protein pyrolyzate and methanol solution, obtained by adding hydrochloric acid to a KCN solution, were determined by the pyridine-pyrazolone method. 7 ) Gas chromatography. The gas chromatograph used was a Hitachi model 063 equipped with a thermal conductive detector.…”