Flow injection analysis of hydrogen peroxide in disinfectants

A flow injection analysis (FIA) method for the automated determination of h ydrogen peroxide in the presence of even stronger oxidants is presented bas ed on the immediate formation of a colored adduct between hydrogen peroxide and a dinuclear iron(III) complex.-A reagent stream with the complex and a carrier stream into which the sample is injected are combined in a low dea d volume mixing tee. A reaction coil provides for a reaction time of 7 s, a fter which detection is performed using UV/vis spectroscopy at 575 nm. Majo r advantages of the method are the simple experimental setup and the high s electivity even towards stronger oxidants. Real samples have been investiga ted and the method has been validated using independent techniques includin g microplate spectrophotometry and HPLC.