Isotope dilution-mass spectrometry determination of blood cyanide by headspace gas chromatography.
A direct and sensitive method for the determination of blood cyanide by isotope dilution was developed. The blood is placed in a headspace vial, and K13C15N is added as internal standard. Addition of phosphoric acid liberates the cyanide as HCN. The detection is accomplished by mass spectrometry after a fine mass calibration tuning. The detection limit obtained is 0.3 micromol/L. The within- and inter-run coefficients of variation are 4.4% (for a concentration of 2.5 micromol/L) and 3.9% (for a concentration of 4.7 micromol/L), respectively. The observed recovery is 98%. A round-robin exercise was carried out to compare the performance of this method with others currently in use in other clinical laboratories.
Dumas
Pierre
P
Laboratoire de Toxicologie, Institut National de Santé Publique du Québec, 945, Avenue Wolfe, 4e étage, Sainte-Foy, Québec, G1V 5B3, Canada. pierre.dumas@inspq.qc.ca
Gingras
Guy
G
LeBlanc
Alain
A
D002849:Chromatography, Gas / Q000295:instrumentation* / Q000379:methods*; D003486:Cyanides / Q000097:blood*; D006801:Humans; D011865:Radioisotope Dilution Technique; D015203:Reproducibility of Results
D003486:Cyanides