MULTIDIMENSIONAL ANALYSIS OF X-RAY FLUORESCENCE SPECTRA AS A POSSIBLE APPROACH FOR A COMPARATIVE STUDY OF THE ELEMENTAL COMPOSITION OF FRUIT AND SEEDS OF MANGIFERA INDICA, ACTINIDIA DELICIOSA, NIGELLA SP.

Relevance. The specificity of plant raw materials as an object of XRF is due to the heterogeneous accumulation of elements at the subcellular and tissue levels – in plants, elements are present in adsorbed, colloidal, ionic forms, as organomineral complexes and polymeric compounds. Thus, the study of plant substrates is limited by the presence of matrix effects, which require a set of standards – reference samples. The purpose of this work is to investigate the degree of interspecific and intraspecific differences in the elemental profiles of plant samples without using a standard by the means of principal component analysis for X-ray fluorescence spectra processing. Material and methods. The proposed approach was applied to study the elemental profiles of fruits genus Actinidia, Mangifera and seeds of plants ge-nus Nigella. The work was performed on an EDX-7000 Shimadzu energy-dispersive X-ray fluorescence spectrometer. For data processing by the princi-pal component method, OriginPro 2017 software (OriginLab, USA) was used. Results. As a result of the work, the efficiency of the principal component method in processing the X-ray fluorescence data is shown. Thus, the anal-ysis of the elemental composition of dried seeds of kiwi fruits showed that the samples, regardless of the region of growth, are quite similar in chemi-cal composition, which, apparently, is species specific. It has been established that the use of XRF to assess the calcium content in the edible part of the fruit according to stable and reproducible results obtained for seeds is promising. On the example of mango fruits, it was shown that the grinding of fruit tissues leads to an increase in the intensity of the fluorescence signal of all elements. It has been shown that X-ray fluorescence analysis doesn’t make it possible to reveal all elements in the composition of the plant matrix, however, the ratio of fluorescence signals adds up to a characteristic and species-specific pattern. Conclusion. The results obtained indicate the possibility of using the technique for express analysis of the elemental composition of plant objects and raw materials, including for the purpose of establishing the type of producing plant or determining its geographical region of origin.