A simple method for glass analysis using total reflection X-ray fluorescence spectrometry

Abstract

In this work, a simple and cost-effective method was developed for Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Ni, Cu, Zn, Rb, Sr, Ba and Pb determination in glass samples employing suspension sampling and total reflection X-ray fluorescence (TXRF). The experimental conditions were optimized using multivariate approach being the optimum conditions located by Derringer's desirability function. Proposed method was validated in accordance with the National Institute of Metrology, Quality and Technology (Inmetro, Brazil). Limit of detection (LD) and limit of quantification (LQ) were adequate for determination of trace elements in glass. The evaluation of the accuracy and precision was realized by analysis of standard reference materials of glass (NIST 612). For the majority of the elements, good agreement was achieved between the certified value and the value obtained in the NIST 612. The relative standard deviation (RSD%) was achieved between 3.6 and 10.3%. Moreover, no significant differences were observed between the proposed method compared to the ICP-MS. After the validation step, the method was applied to 31 glass samples and with aid of an exploratory principal component analysis (PCA), a perfect discrimination of the glass from originally manufactured smartphones was obtained. In addition, soda-lime glass could be reasonably distinguished from smartphone screens. The developed method is fast, consumes low amounts of reagents and allows the determination of many analytes simultaneously. Additionally, the method does not require calibration curves. Therefore, TXRF proved to be attractive and useful for routine analysis of glass.