In vitro Monitoring of Macro and Microelements in Multimineral Preparations across Dissolution Profiles by Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES)

In this study, inductively coupled plasma optical emission spectrometry (ICP OES) was used for multi-element analysis in five multimineral preparations from a dissolution test, in accordance with the United States Pharmacopeia (USP 34 method): apparatus 1, 75 rpm and 900 mL of 0.1 mol L-1 HCl. Element releases in all samples (minimum-maximum in %) were: Ca (14.5-28.2), Cr (54.5-68.0), Cu (2.9-10.0), Fe (4.0-34.3), Mg (6.0-25.2), Mn (2.6-51.2), V (0.0-51.4) and Zn (1.5-107.3). The concentrations of Al, Ba, Cd, Co, Mo, Pb and Se were below the limit of detection of ICP OES. Accuracy was assessed by microwave digestion and recovery values of 94-102%. USP 34 method indicates that not less than 75% of the elements described on the product label must be dissolved in 1 h. Only the release of Zn met the recommendations. The results indicated the need for greater quality control in multivitamin preparations. The dissolution test was validated in order to contribute to Brazilian and other pharmacopoeias.