NCJ Number
221681
Journal
Journal of Forensic Sciences Volume: 52 Issue: 6 Dated: November 2007 Pages: 1401-1407
Date Published
November 2007
Length
7 pages
Annotation
This study compared the quantitative determination of blood cyanide in two cases of fatal intoxication in two different laboratories, with one laboratory using the spectrophotometric method (VIS) and the other laboratory using the headspace gas chromatographic method with nitrogen-phosphorus detector (HS-GC/NPD).
Abstract
The comparison of the two methods for quantifying blood cyanide showed that the results obtained with the two procedures were insignificantly different. They compared favorably and were deemed suitable by the authors for the rapid diagnosis of cyanide in postmortem cases. In the classical spectrophotometric method, hydrogen cyanide (HCN) was quantitatively determined by measuring the absorbance of chromophores that formed as a result of interaction with chloramine T. Three calibration lines were constructed by using six calibrators in the cyanide range 0.5-10 mg/ml. The limit of detection was assessed by analyzing three blank samples and calculating the standard deviation of the responses. In the automated HS-GC/NPD method, blood was placed in a headspace vial; internal standard (acetonitrile) and acetic acid were then added. This resulted in cyanide being liberated as HCN. The VIS and HS-GC/NPD methods were validated on postmortem blood samples fortified with potassium cyanide in the ranges of 0.5-10 and 0.05-5 mg/ml, respectively. Detection limits were 0.2 mg/ml for VIS and 0.05 mg/ml for HS-GC/NPD. After brief descriptions of the circumstances of the two cases, procedures of the blank sample collection and storage are presented. 3 figures and 10 references