Abstract
In the present work, the microwave digestion procedure for the determination of Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Se, V and Zn in multivitamin/multielement (MVM) preparations used for pregnant women and diabetics employing ICP-MS, was optimized by factorial design 33 (27 runs). The microwave digestion conditions temperature (160, 180 and 200 degrees C), acid mixture volume (3.9, 5.2 and 6.5 ml) and radiation period (10, 15 and 20 min) were selected as factors. Moreover, a multiple response (MR) was built to establish a compromise conditions between the elements. The optimum conditions were found to be 160 degrees C, 6.5 ml, and 20 min for temperature, acid mixture volume and radiation period, respectively. The procedure was validated using standard reference material (SRM3280) and elements recoveries were found to be in the range 88 -107% and was applied to determination of Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Se, V and Zn in commercial MVM samples obtained from the local market.