Influence of measurement mode on the results of glioblastoma multiforme analysis with the FTIR microspectroscopy

Aleksandra Wilk; Agnieszka Drozdz; Karolina Olbrich; Natalia Janik-Olchawa; Zuzanna Setkowicz; Joanna Chwiej

doi:10.1016/j.saa.2022.122086

Influence of measurement mode on the results of glioblastoma multiforme analysis with the FTIR microspectroscopy

Spectrochim Acta A Mol Biomol Spectrosc. 2023 Feb 15;287(Pt 2):122086. doi: 10.1016/j.saa.2022.122086. Epub 2022 Nov 8.

Authors

Aleksandra Wilk¹, Agnieszka Drozdz², Karolina Olbrich¹, Natalia Janik-Olchawa¹, Zuzanna Setkowicz³, Joanna Chwiej¹

Affiliations

¹ Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Mickiewicza 30, 30-059 Krakow, Poland.
² Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Mickiewicza 30, 30-059 Krakow, Poland; Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin, Poland. Electronic address: adrozdz@agh.edu.pl.
³ Institute of Zoology and Biomedical Research, Jagiellonian University, Gronostajowa 9, 30-387 Krakow, Poland.

PMID: 36423418
DOI: 10.1016/j.saa.2022.122086

Abstract

Fourier Transform Infrared (FTIR) microspectroscopy is well known for its effectiveness in spectral and biochemical analyses of various materials. It enables to determine the sample biochemical composition by assigning detected frequencies, characteristic for functional groups of main biological macromolecules. In analysis of tissue sections one of two measurement modes, namely transmission and transflection, is usually applied. The first one has relatively straightforward geometry, hence it is considered to be more precise and accurate. However, IR-transparent media are very fragile and expensive. Transflection does not require expensive substrates, but is more prone to disruptive influence of Mie scattering as well as electric field standing wave effect. The excessive comparison of spectra' characteristics, obtained via both measurement modes, was performed in this paper. By the means of Mann-Whitney non-parametrical U test and PCA, the comparison of results obtained with both modes and assessment of usefulness of IR spectra obtained with transmission and transflection modes to differentiate between healthy and GBM-affected tissue, were performed. The main objective of the presented research is to compare the results of FTIR analysis of unfixed biological samples performed with transflection and transmission mode. In frame of the study we demonstrated the discrepancies between results of biochemical analysis performed based on data obtained with transmission and transflection. Such observation suggests that caution should be taken in drawing conclusions from the results obtained with transflection geometry, as its more prone to disruptive effects. Despite that, IR spectra developed with both modes allowed to distinguish GBM area from healthy tissue, which proves their diagnostic potential. Especially, application of the ME-EMSC correction of spectra before PCA enhances the performance of both methods to distinguish the analysed tissue areas.

Keywords: GBM; Glioblastoma multiforme; ME-EMSC; PCA; Transflection; Transmission; U87MG.

MeSH terms

Electricity
Fourier Analysis
Glioblastoma* / diagnosis
Humans
Spectrophotometry, Infrared
Spectroscopy, Fourier Transform Infrared