Modified Determination Method of Total Bromine in Agricultural Products by Gas Chromatography

摘要

In the official method for determination of total bromine in fruit and grain foods, bromine is derivatized with 3-pentanone for GC analysis. Co-existing substances sometimes interfere with measurement of the derivative, though the method is highly selective. In this study, the notification method was modified to reduce impurity peaks by applying 3-hexanone. Samples were alkalized and reduced to ash in an electric furnace. After ashing, samples were oxidized with potassium permanganate solution and derivatized with 3-hexanone. The calibration curve was linear from 0.1 mu g/mL up to 5.0 mu g/mL. The detection limit (S/N= 10) was 0.1 mu g/mL, i.e., 5 mu g/g for herb, 2.5 mu g/g for grains and 1.0 mu g/g for fruits. The recoveries of bromine from fruit,grain foods and herbs added at the levels of 5 to 25 mu g/g ranged from 84.2 to 96.9%. The values of relative standard deviation (RSD) were from 1.4 to 6.3%. This method should be useful for routine examination of total bromine in foods.