Evaluation of different calibration methods in inductively coupled plasma atomic emission spectrometric analysis of certified glass materials and archaeological glass specimens

Abstract

An extended study of the effect of the calibration strategy followed in multi-element analysis of glass matrices by inductively coupled plasma atomic emission spectrometry (ICP-AES) is reported. The accuracy of the determination of two major (Ca, Na) and four minor constituents (Al, Fe, Mg, Ba) was evaluated by analyzing two certified reference glass materials (SRM 620 and SRM 621) by three different calibration methods, including multi-element and single-element standards. The effect of sample dilution and the presence of high concentrations of some major constituents was also investigated. Two-way analysis of variance was applied at a given level of confidence (95%) to evaluate the significance of these effects as sources of variation, while the slope of the calibration curves was used as a reliable criterion for the evaluation of the different calibration processes. The recoveries obtained from the two SRMs were also found. Finally, the three calibration methods were applied successfully in the analysis of archaeological glass fragments and glassy specimens from an excavated ancient oven.