ETV-ICP-OES DETERMINATION OF ESSENTIAL, NON-ESSENTIAL AND TOXIC ELEMENTS IN SEVEN BULGARIAN HERBS

The content of essential, non-essential and toxic elements in seven commercially available and widely consumed for medicinal purposes Bulgarian herbs was determined by means of an optimized electrothermal vaporization inductively coupled plasma optical emission spectrometric (ETV-ICP-OES) method in one run. Plasma observation was axial and torch arrangement was horizontal. The halogenating agent CHF3 was used as modifier gas. Calibration was performed with evaporated aqueous standard solutions and solid certified reference materials of plant origin. For each analyte all calibration points were covered by one corresponding calibration curve. Thus it was proved that no matrix effects were observed under the optimized conditions. Results for the concentrations of altogether 26 main, minor and trace elements in the investigated samples were obtained with precision in most cases better than 10% RSD. ETV-ICP-OES proved to be a reliable method for the simultaneous and matrix free determination of essential, non-essential and toxic elements in medicinal plants.