Comparison of methods for preparation of artificial samples of a known concentration for X-ray fluorescence analysis of plants

The study presents a comparative analysis of methods for preparing emitters of known concentration for quantitative X-ray fluorescence analysis of heavy metals in plant samples. Artificial reference samples were prepared on the basis of certified reference materials of plants to preserve matrix effects, inter-element influences, and obtain a similar density of emitters. Target elements (Sr, Pb, Zn, Cu, Ni, Co, Fe, Cr and Ba) were added to certified reference materials in the form of ion solutions in three ways: by evaporation of the solvent when heated at atmospheric pressure; by evaporation at reduced pressure in a rotary evaporator; by successive evaporation of the solvent followed by ashing and fusing the ash residue with borate fluxes in one crucible. Based on the resulting calibration curves, the coefficient of determination, the standard deviation, 95% confidence interval for the calibration curves, relative standard error, and the average coefficient of alienation were calculated. The X-ray fluorescence analysis results for a test set of plant samples, obtained using these calibration curves, agreed well with the results from inductively coupled plasma atomic emission spectroscopy analysis of the same plant samples. The distribution of the added elements in materials obtained by evaporation of solutions was analyzed using scanning electron microscopy (SEM). The analysis revealed that added elements were uniformly distributed as fine particles (<1 µm) regardless of evaporation method, while inherent plant mineral elements (Si, Ca, K, Al) formed larger discrete particles.

Sverchkov I. P. Comparison of methods for preparation of artificial samples of a known concentration for X-ray fluorescence analysis of plants. MIAB. Mining Inf. Anal. Bull. 2026;(12):100-117. [In Russ]. DOI: 10.25018/0236_1493_2026_12_0_100.

This investigation was financially supported by the Ministry of Science and Higher Education of the Russian Federation (FSRW-2024-0005).

I.P. Sverchkov, Cand. Sci. (Eng.), Senior Researcher, Empress Catherine II Saint-Petersburg Mining University, 199106, Saint-Petersburg, Russia, e-mail: sverchkov_ip@pers.spmi.ru, ORCID ID: 0000-0003-4725-0050.

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