Determination of Thiocyanate Ion in Saliva

A simple, fast and relatively inexpensive UV-Vis spectrophotometric method for the indirect determination of thiocyanate ion in saliva, obtained by the absorbance of ferric thiocyanate which was attained by the reaction of thiocyanate ion and ferric ion, is proposed. The influences of acidity, reaction time and temperature were studied. Under the optimized operating conditions, the relative standard deviations were smaller than 0.89%, the linear range of quantification of thiocyanate was 0.5~30.0 mg·L^-1 with the regression coefficient (r²) of 0.9993, and the recovery was found to be 90.9%~110.8%. The present method was successfully applied to the rapid determination of thiocyanate in human saliva