Sequential Determination of 13 Elements in Complex Matrices by Stripping Voltammetry with Mixed Complexing Electrolytes

This paper presents the determination of 13 elements in a simultaneous and sequential analysis using solochrome violet (SVRS), chloranilic acid (CA), diethylenetriaminepentaacetic acid (DTPA), dimethylglyoxime (DMG), and oxine as complexing electrolytes. The Methods were applied to determine Al³⁺, Fe³⁺, Mo⁶⁺, Zn²⁺, Cd²⁺, Pb²⁺, Cu²⁺, Ni²⁺, Co²⁺, Tl⁺, U⁶⁺, V⁵⁺, and Cr⁶⁺ in fertilizers, plant materials, and foodstuffs. The Method was found to be selective and accurate (82.13–119.03 %) for elemental analysis in complex matrices that were previously submitted to a total oxidative digestion step (calcination and wet digestion). Mutual interferences of the elements were systematically investigated. The Sequential Method could be useful for the routine quality control of foodstuffs and fertilizer formulations regarding mineral nutrients or contaminants.