Optimization and validation of an inductively coupled atomic emission spectrometry method for macro- and trace element determination in berry fruit samples
The aim of this paper was the optimization and validation of an inductively coupled atomic emission method (ICP-AES) for macro- and trace element determination in berry samples. To optimize the atomization and ionization processes in an inductively coupled plasma source, the Mg(II) 280.270 nm/Mg(I) 285.213 nm (Mg(II)/Mg(I)) line intensity ratio was used for both viewing (axial and radial) modes. In particular, the effects of the power and the carrier gas flow rate are described. The power was varied from 750 kW to 1350 kW in intervals of 100 kW. The nebulizer argon flow rate was increased from 0.5 mL min−1 to 1.5 mL min−1 in intervals of 0.5 mL min−1. The Mg(II)/Mg(I) ratio at an applied power of 1150 W and a nebulizer gas flow rate of 0.5 L min−1 for axially and radially viewed configurations was 10.57 and 12.06, respectively. The validation process of the developed method involved precision, accuracy, linearity of the calibration curve, limit of detection (LOD) and limit of quantification (LOQ). Accurate results were found for a certified reference material. In analyzed samples, 20 elements were studied and 18 (Ca, K, Mg, P, Na, Al, B, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, Si, and Zn) elements were determined quantitatively. Potassium is the metal with major content, followed by Ca, P, Mg, Na and other micro-elements, such as Mn, Fe, Cu, Zn and Si. According to the toxic element contents, the investigated samples are considered safe for human consumption. Generally, berry samples are significant sources of elements that are essential to human health and diet.