Evaluation of Mineral Supplements for Content and Purity by Flame/Graphite Furnace AAS

Accurate analysis of metals in vitamin/mineral preparations and food supplements is extremely important given that doctors, dieticians and health officials recommend a balanced diet that provides essential minerals to the human body. There is a need to quantitate these elements easily and reproducibly. For instance ferrous gluconate is a source of iron but can be contaminated with manganese, titanium and vanadium. For this reason, examining over-the-counter and prescription formulations is necessary as there are potential contaminants present in higher concentration minerals. Graphite furnace atomic absorption spectroscopy (GFAAS) with deuterium background correction (D2) is one of the few acceptable techniques for error-free determination of trace metals and micro-minerals, whilst electrolyte metals and minor minerals are generally tested by simple flame AA (FAAS). However, both flame and furnace techniques can suffer from interference when low level elements are determined in complex matrices. Alkali elements can create background effects that will add significant inaccuracies to an analysis. Also, contributing to analytical errors is the formation of smoke particulates in a graphite furnace analysis caused by the presence of organic materials in the sample matrix. This application notes demonstrates that interferences in these traditional analysis methods can be compensated by the use of a D2 Background Correction system, and the unique design of the Buck 210VGP AA System.