Abstract

The effects of different parameters and the nitric acid concentration on the sensitivity and repeatability of elemental analysis were characterized for liquid electrode plasma optical emission spectrometry (LEP-OES). In addition, internal standardization for LEP-OES was investigated. The developed LEP-OES method was used for the determination of lithium, potassium, iron, and zinc in aqueous solutions and in samples with high acid concentrations after microwave-assisted digestion. The results were compared with those obtained by inductively coupled plasma — optical emission spectrometry. The sensitivity was improved when the plasma parameters were optimized. In addition, some improvement in the accuracy and reproducibility of the results was achieved when internal standardization by gold was employed. However, due to the strong matrix effects, the calibration standards should be made as similar as possible to the sample matrix.