Spectrophotometric Determination of Sodium Thiocyanate in Infant Food

A spectrophotometric method for determination of sodium thiocyanate in infant food was proposed. Experimental conditions, including methods of dissolution for different samples, time of ultrasonic treatment and precipitant for protein, were described in detail. A red colored coordination complex between SCN- and Fe3+ was formed, with its max. absorption at the wavelength of 457 nm. Linear relationship between values of absorbance and mass concentration of sodium thiocyanate was found in the range within 20 mg·L-1, with detection limit of 1.670 g·kg-1. The proposed method was applied to the determination of sodium thiocyanate in infant food, giving values of recovery in the range of 91.8%-98.7%.