DETERMINATION OF THIOCYANATE BY CARBONYL SULFIDE (OCS) GENERATION ANDGAS-PHASE MOLECULAR ABSORPTION SPECTROMETRY

A method for determination of thiocyanate by gas-phase molecular absor ption spectrometry is described. The proposed method is based on the c ontinuous generation of carbonyl sulphide and preconcentration in a li quid nitrogen trap. Later, the product is volatilised and the absorban ce at 224 nm is measured. Under the optimised conditions, the calibrat ion graph was linear for 2-80 mu g ml(-1), with a detection limit of 1 mu g ml(-1). No metal ions interfered. The method was tested with sal iva samples from non-smokers and smokers; the results show that it is possible to distinguish between these two categories of individuals.