Study and Application on the Complexing Colouration Reaction of Selenium with Magneson I

A new spectrophotometric method for the determination of trace selenium in table salt was introduced.The proposed method was based on the complexing colouration reaction of Se(IV) with magneson I to form a stable complex(1∶7) in borax buffer solution at pH 9.6.The maximum absorption wavelength was at 560 nm.Beer's law was obeyed in the range of 0μg/mL and 1.2μg/mL for selenium determination.The apparent molar absorptivity was found to be 4.04×104 L/mol·cm.The limit of detection was 0.08 μg/mL for selenium.The proposed method was applied to determine selenium in salt fortified with selenium.RSD was 1.51%(n=5),and the average recovery was 99.7%.