Original Articles: 2019 Vol: 11 Issue: 12
Optimized Microwave Digestion Method for Some Micro and Macro Elements in Pregnant Women and Diabetics Multivitamin/Multielement Preparations
Abstract
The goal of the current study was to obtain an optimum microwave decomposition conditions allowing the determination of several minerals (Fe, Mg, Zn, Cu and Mn by FAAs, and Cr and Se by GFAAs) in pregnant women and diabetic Multivitamin/Multielement (MVM) preparations. Optimum conditions were found to be 0.1 g of sample powder, and digested samples with 5 ml of HNO3, 0.5 ml of HCl and 1 ml of H2O2 and subjected to radiant microwave heating. A pretreatment, using a three-step heating program, irradiation from 10 minutes to 500W; irradiation from 16 minutes to 600W; and cooling. And a reactant of the oxidizing acid mixture was suitable for determining the seven metals studied without subsequent manipulation of the digestion product. The accuracy of the procedure was verified using three spiked samples at three different levels, and recoveries of Fe, Zn, Mn, Mg, Cu, Cr and Se were found to be in the range 98.59 ± 0.36-100.91 ± 0.61%, 99.05 ± 0.46-101.19 ± 0.56%, 97.30 ± 0.1-100.57 ± 0.09%, 97.50 ± 5.63-99.10 ± 3.62%, 98.93 ± 0.05-100.12 ± 0.057%, 99.136 ± 0.01-100.13 ± 0.02%, and 98.54 ± 0.07-99.85 ± 0.03%, respectively. The optimized method was validated and applied to the determination of Fe, Mg, Zn, Cu, Mn, Cr and Se in eight available commercially MVM capsules obtained from local market.