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.

摘要

骨骼主要是矿物（磷灰石）和有机（胶原）部分的等体积分数的复合材料。它们的红外光谱特性反映了它们的成分。骨成岩是通过化学降解使钙化组织沉积后的变化。这是一个复杂的过程，并受众多外部和个人因素的影响。已使用傅里叶变换红外（FTIR）光谱学来确定成岩轨迹，以监测生物磷灰石的保存状态。我们使用衰减全反射（FTR）FTIR光谱技术研究了从两个不同地点-Sakkara和Aswan收集的四个朝代的古埃及骨骼的成岩作用。尽管后者是一种极有前景的技术，因为它是一种破坏力最小的工具，但样品的物理性质可能会影响数据的准确性。研究的骨块来自两个部位，即杆身和股骨头。透射电子显微镜（TEM）用于研究骨晶体的大小和形状。ATR-FTIR光谱仪显示Sakkara和Aswan土壤样品之间的分子指纹不同。该技术能够监测整个轴骨的不同分子结构，表明不同的成岩等级。TEM显微照片显示，晚期轴状骨的针状晶体含量较低，而罗马希腊时期的则具有大量不规则的薄血小板晶体。ATR-FTIR光谱仪显示Sakkara和Aswan土壤样品之间的分子指纹不同。该技术能够监测整个轴骨的不同分子结构，表明不同的成岩等级。TEM显微照片显示，晚期轴状骨的针状晶体含量较低，而罗马希腊时期的则具有大量不规则的薄血小板晶体。ATR-FTIR光谱仪显示Sakkara和Aswan土壤样品之间的分子指纹不同。该技术能够监测整个轴骨的不同分子结构，表明不同的成岩等级。TEM显微照片显示，晚期轴状骨的针状晶体含量较低，而罗马希腊时期的则具有大量不规则的薄血小板晶体。