Catalytic kinetic spectrophotometric determination of trace iron III with orange G and potassium periodate

A new catalytic kinetic method based on remarkable catalytic action of Fe*# on the oxidative fading reaction between orange G and KIO 4 in sulfuric acid medium for the determination of trace Fe*# was established. The optimal conditions and the kinetic parameters were investigated. The linear range for the determination of Fe 3+ by the proposed method is 0.000 2-0.032 μg/mL,the detection limit is 5.34×10 -10 g/mL. The method has been used for the determination of trace iron*# in the chinese herbal medicines and foods with satisfactory results.