Comprehensive approach to the validation of the standard method for total reflection X-ray fluorescence analysis of water

Laura Borgese; Rogerta Dalipi; Alessandro Riboldi; Fabjola Bilo; Annalisa Zacco; Stefania Federici; Maurizio Bettinelli; Elza Bontempi; Laura Eleonora Depero

doi:10.1016/j.talanta.2017.12.087

Comprehensive approach to the validation of the standard method for total reflection X-ray fluorescence analysis of water

Talanta. 2018 May 1:181:165-171. doi: 10.1016/j.talanta.2017.12.087. Epub 2018 Jan 4.

Authors

Laura Borgese¹, Rogerta Dalipi², Alessandro Riboldi³, Fabjola Bilo³, Annalisa Zacco³, Stefania Federici³, Maurizio Bettinelli⁴, Elza Bontempi³, Laura Eleonora Depero³

Affiliations

¹ INSTM & Chemistry for Technologies Laboratory, Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy. Electronic address: laura.borgese@unibs.it.
² INSTM & Chemistry for Technologies Laboratory, Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy; Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, B. Ubertini, Via Antonio Bianchi, 7/9, 25124 Brescia, Italy.
³ INSTM & Chemistry for Technologies Laboratory, Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy.
⁴ UNICHIM, Associazione per l'Unificazione nel Settore dell'Industria Chimica, Italy.

PMID: 29426496
DOI: 10.1016/j.talanta.2017.12.087

Abstract

In this work, we present the validation of the chemical method for total reflection X-ray fluorescence (TXRF) analysis of water, proposed as a standard to the International Standard Organization. The complete experimental procedure to define the linear calibration range, elements sensitivities, limits of detection and quantification, precision and accuracy is presented for a commercial TXRF spectrometer equipped with Mo X-ray tube. Least squares linear regression, including all statistical tests is performed separately for each element of interest to extract sensitivities. Relative sensitivities with respect to Ga, as internal standard, are calculated. Accuracy and precision of the quantification procedure using Ga as internal standard is evaluated with reference water samples. A detailed discussion on the calibration procedure and the limitation of the use of this method for quantitative analysis of water is presented.

Keywords: Calibration; Elements; TXRF; Validation; Water.