Method validation for chemical composition determination by electron microprobe with wavelength dispersive spectrometer

2nd International Congress of Mechanical Engineering and Agricultural Science

机械制造;农业科学

Herrera-Basurto, R.^1 ; Mercader-Trejo, F.^2 ; Muñoz-Madrigal, N.^1 ; Juárez-García, J.M.^3 ; Rodriguez-López, A.^2 ; Manzano-Ramírez, A.^4

Universidad Aeronáutica en Querétaro, Qro., Carretera Estatal 200 Queretaro-Tequisquiapan No. 22154, Colón, Querétaro

C.P. 76270, Mexico^1

Universidad Politécnica de Santa Rosa Jáuregui, Carr. Federal 57, km 31-150 QRO-SLP, Santa Rosa Jáuregui, Querétaro, Qro.

76220, Mexico^2

Centro Nacional de Metrología, km 4, 5 carretera a Los Cués, Municipio del Marqués, Querétaro

76246, Mexico^3

CINVESTAV-Qro, Libramiento Norponiente No. 2000, Fraccionamiento Real de Juriquilla, Querétaro, Qro

76230, Mexico^4

关键词: Analytical method validation;    Chemical compositions;    Elemental compositions;    Impurity determination;    ISO/IEC 17025 standard;    Uncertainty estimation;    Validation parameters;    Wavelength dispersive spectrometers;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/138/1/012003/pdf
DOI  :  10.1088/1757-899X/138/1/012003

学科分类：农业科学（综合）

来源: IOP

【 摘 要 】

The main goal of method validation is to demonstrate that the method is suitable for its intended purpose. One of the advantages of analytical method validation is translated into a level of confidence about the measurement results reported to satisfy a specific objective. Elemental composition determination by wavelength dispersive spectrometer (WDS) microanalysis has been used over extremely wide areas, mainly in the field of materials science, impurity determinations in geological, biological and food samples. However, little information is reported about the validation of the applied methods. Herein, results of the in-house method validation for elemental composition determination by WDS are shown. SRM 482, a binary alloy Cu-Au of different compositions, was used during the validation protocol following the recommendations for method validation proposed by Eurachem. This paper can be taken as a reference for the evaluation of the validation parameters more frequently requested to get the accreditation under the requirements of the ISO/IEC 17025 standard: selectivity, limit of detection, linear interval, sensitivity, precision, trueness and uncertainty. A model for uncertainty estimation was proposed including systematic and random errors. In addition, parameters evaluated during the validation process were also considered as part of the uncertainty model.