ESTIMATION OF BROMATE IN FLOUR AND FLOUR PRODUCTS BY ION CHROMATOGRAPHY USING POST COLUMN DERIVATIZATION METHOD WITH TRIIODIDE

Abstract

In this study, a method is established for the evaluation of bromate residues in flour and flour products. Water is used to extract bromate from the bulk product. To remove the co-extractives that hinder Ion Chromatography (IC) and deteriorate the IC column, successive steps were taken. Bromate was separated using an IonPac AS19 column with NaOH gradient elution and detected after post-column reaction to form triiodide and UV absorbance. The investigations on the samples validate the recoveries of spiked standard as 63.2–105.0%, limit of detection (LOD) 0.5 µg/L, and relative standard deviations (RSD) <9.2%. Consequently, the assay can be applied to determine bromate in flour and flour products at trace contamination levels.

Keywords:

• bromate
• flour and flour products
• ion chromatography (IC)
• high capacity column
• post-column derivatization
• triiodide

Notes

^a at spiked low-level of 6.0 ng/mL.

^b at spiked medium-level of 20.0 ng/mL.

^c at spiked high-level of 200.0 ng/mL.