Research on residual determination of bromate in flour and flour products by Ion chromatography

Objective:To establish a method for residual determination of bromate in flour and its products by ion chromatography.Methods:Bromate was first extracted from the sample by water bath heating and purified by a silver column,then determined by ion chromatography.Chromatographic separation was carried out on Ionpac AS19 column(250 mm×4 mm i.d.,5 μm) with ASRS-ULTRAⅡ anion suppressor,and a DS6 suppressed conductivity detector was used to the determination,and potassium hydroxide was used in gradient elution.Results:The linear range was 1.0 μg/ml～6.0 μg/ml for bromate with correlation coefficients of more than 0.999.When the signal to noise ratio equals to 3,the limits of quantitation were found to be 0.1 mg/kg.Conclusion:The developed method was satisfied with the residual determination for bromate in flour and its products.