Investigating Egyptian archeological bone diagenesis using ATR-FTIR microspectroscopy

Abstract

Bones are mainly composite materials of equivalent volume fractions of mineral (apatite) and organic (collagen) parts. Their infrared spectroscopic characteristics mirror their composition. Bone diagenesis is the post-depositional changes of calcified tissues by chemical degradation. It is a complicated process and affected by numerous external and individual factors. Diagenetic trajectories have been employed using Fourier transform infrared (FTIR) spectroscopy to monitor the preservation status of bioapatite. We studied the diagenesis in ancient Egyptian bones of four dynasties collected from two different locations -Sakkara and Aswan using attenuated total reflectance (ATR) FTIR microspectroscopy. Despite the latter is a promising technique since it is a minimally destructive tool, the samples' physical properties may affect the data accuracy. The studied bone pieces were from two sites, the shaft and the femur head. Transmission electron microscopy (TEM) was used to investigate the bone crystals size and shape. ATR-FTIR spectrographs showed different molecular fingerprints between Sakkara and Aswan soil samples. The technique was able to monitor different molecular structures across the shaft bones indicating different diagenetic grades. TEM micrographs showed low abundant crystals of needle shaped for Late period shaft bones, while those from Roman Greek period were characterized with abundant irregular thin platelet crystals.

Infrared Spectroscopy to Analyze Sexual Dimorphism of Hard Dental Tissue Maturation at Eruption in Patients with Connective Tissue Dysplasia

“…This absorption band can be used as a good indicator of any changes in the environment if it is shifted to lower frequencies and at reduced the absorbance. 61 In addition, structural changes and protein anomalies may indicate insufficient mineralization of the teeth at the eruption stage.…”

Optimizing the biomimetic synthesis of hydroxyapatite for the consolidation of bone using diammonium phosphate, simulated body fluid, and gelatin

“…(1) 10Ca 2+ + 6HPO 2− 4 + 8OH − → Ca 10 (OH) 2 (PO 4 ) 6 ↓ + 6H 2 O Tricalcium phosphate (TCP) 1.5 K sp = 1 × 10 -26 α: αmorphous β: rhombohedral X-ray diffractometry (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) are the main techniques for characterizing the condition of archaeological bone in the burial environment [34][35][36][37][38][39], as well as HAP, in particular [13,30]. In s-HAP, peaks are well-resolved, while in n-HAP and c-HAP, imperfections in the crystal lattice are reflected in broader envelopes [31,40].…”