Determination of thiocyanate in plasma and saliva without deproteinisation and its validation as a smoking parameter.
A simple photometric procedure was developed for the determination of thiocyanate (SCN-) in plasma and saliva without deproteinisation or dialysis. Fe(III) ions form a red coloured complex with SCN- with a maximum absorbance at 460 nm. Mercury(II) nitrate is used to run a sample blank. A manual and an automated version (COBAS BIO) of the method is described. The method is linear up to 5000 mumol/l SCN-. The CV of the between-run precision is 2.8-8% for the manual and 2.6-6.6% for the automated method. The SCN- plasma concentration was 21-134 mumol/l in nonsmokers and 44-260 mumol/l in smokers. In mixed saliva, the concentration is much higher than in plasma: 1.57-5.5 mumol/l in smokers and 0.79-3.9 mumol/l in nonsmokers. Plasma, but not oral fluid SCN-, is a valuable parameter for studying smoking habits in population surveys. However, its use is limited. In our experience only heavy smokers can be distinguished from nonsmokers.
Degiampietro
P
P
Chemisches Zentrallabor der Universitätskliniken, Inselspital Bern.
Peheim
E
E
Drew
D
D
Graf
H
H
Colombo
J P
JP
D005260:Female; D006801:Humans; D007202:Indicators and Reagents; D008297:Male; D010306:Parotid Gland / Q000378:metabolism; D010783:Photometry; D012463:Saliva / Q000032:analysis*; D012907:Smoking / Q000378:metabolism*; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013861:Thiocyanates / Q000032:analysis* / Q000097:blood
D007202:Indicators and Reagents; D013861:Thiocyanates