Primera Aproximación al uso de FTIR para Caracterizar Hueso Humano Afectado por Enfermedades Granulomatosas Crónicas

Abstract

Chronic granulomatous infections are a relevant topic in Paleopathology. Abundant literature exists on macroscopic features, but knowledge on bone molecular alterations is still scarce. Here we present an early stage investigation on changes in bone composition and structure using FTIR Fourier-transform infrared spectroscopy, a non-destructive technique that requires small amounts of sample. We sampled vertebrae from five individuals recovered in the necropolis of Plaza de España (Écija, Seville), which presented lesions compatible with TB (3) and brucellosis (2). Affected and non-affected areas of each vertebra were analysedusing FTIR-KBr (20 samples). Additionally, we calculated four indices (crystallinity, mineral maturity, carbonate/phosphate, collagen/phosphate). All spectra showed the characteristic vibrational bands ofbone components (phosphate, carbonate and collagen), although affected tissue have higher intensity of carbonate and lower intensity in phosphate absorbances, compared to non-affected samples. We didnot find differences in crystallinity but mineral maturity and the other two ratios were consistently lower (maturity) or higher (the ratios) in affected samples. Altogether, the results suggest that affected bone tissues have a lower content of bioapatite with lower degree of maturity.