DEVELOPMENT OF ANALYTICAL METHODOLOGIES BASED ON ATR FTIR INFRARED SPECTROSCOPY AND MASS SPECTROMETRY WITH MULTIVARIATE ANALYSIS IN THE DIAGNOSIS OF SARCOPENIA
Osteosarcopenia; Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR); Mass Spectroscopy; Multivariate Analysis
This thesis demonstrates the development of new analytical methodologies that combine infrared spectroscopy with attenuated total reflection Fourier transform (ATR-FTIR) and instrumental readings with multivariate classification and variable selection, applied to blood plasma samples for detection of the osteosarcopenia. Within the execution of the work, the studies carried out in this thesis explored infrared spectroscopy with attenuated total reflection Fourier transform (ATR-FTIR) and Paper-Spray Ionization Mass Spectrometry (PSI-MS) to obtain spectra from the blood plasma of patients with and without osteosarcopenia, and the processing of these spectral data by multivariate analysis models. In a first study, ATR-FTIR spectroscopy was used to obtain blood plasma spectra from healthy elderly individuals and patients with sarcopenia. Multivariate classification models were constructed, aiming at a diagnostic methodology for screening elderly sarcopenic patients. The PCA-LDA, PCA-QDA, PCA-SVM, SPA-LDA, SPA-QDA and SPA-SVM algorithms were applied as classification tools and their performance compared. In general, the results obtained through the PCA-SVM variable selection algorithm were the most satisfactory, reaching a sensitivity of 89%, thus being able to be related to functional groups belonging to different biomolecules and possible biomarker.