Nondestructive Analysis of Mummification Balms in Ancient Egypt Based on EPR of Vanadyl and Organic Radical Markers of Bitumen,Analytical Chemistry

当前位置： X-MOL 学术 › Anal. Chem. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Nondestructive Analysis of Mummification Balms in Ancient Egypt Based on EPR of Vanadyl and Organic Radical Markers of Bitumen
Analytical Chemistry ( IF 6.7 ) Pub Date : 2020-11-16 , DOI: 10.1021/acs.analchem.0c03116
Charles E. Dutoit ₁ , Laurent Binet ₁ , Hitomi Fujii ₂ , Agnes Lattuati-Derieux ₂ , Didier Gourier ₁

Affiliation

The black matter employed in the funeral context by ancient Egyptians is a complex mixture of plant-based compounds with variable amounts of bitumen. Asphaltene, the most resistant component of bitumen, contains vanadyl porphyrins and carbonaceous radicals, which can be used as paramagnetic probes to investigate embalming materials without sample preparation. Electron paramagnetic resonance (EPR) at the X-band, combining in-phase and out-of-phase detection schemes, provides new information in a nondestructive way about the presence, the origin, and the evolution of bitumen in these complex materials. It is found that the relative EPR intensity of radicals and vanadyl porphyrins is sensitive to the origin of the bitumen. The presence of nonporphyrinic vanadyl complexes in historical samples is likely due to the complexation of VO²⁺ ions by carboxylic functions at the interface between bitumen and other biological components of the embalming matter. The absence of such oxygenated vanadyl complex in natural bitumen and in one case of historical human mummy acquired by a museum in the 19th century reveals a possible, nondocumented, ancient restoration of this mummy by pure bitumen. The linear correlation between in-phase and out-of-phase EPR intensities of radicals and vanadyl porphyrins in balms and in natural bitumen reveals a nanostructuration of radicals and vanadyl porphyrin complexes, which was not affected by the preparation of the balm. This points to the remarkable chemical stability of paramagnetic probes in historical bitumen in ancient Egypt.

中文翻译：

基于钒氧烷和有机沥青标记的EPR对古埃及木乃伊香脂的无损分析

古埃及人在葬礼中使用的黑物质是植物基化合物与可变数量沥青的复杂混合物。沥青是沥青中最具抵抗力的成分，其中含有钒基卟啉和碳原子团，可用作顺磁性探针，无需样品制备即可研究防腐材料。X波段的电子顺磁共振（EPR）结合了同相和异相检测方案，以无损方式提供了有关这些复杂材料中沥青的存在，起源和演变的新信息。发现自由基和钒基卟啉的相对EPR强度对沥青的来源敏感。历史样品中非卟啉钒基络合物的存在可能是由于VO的络合羧基与²⁺离子在沥青和防腐物质的其他生物成分之间的界面处起作用。在天然沥青中不存在这种氧化的钒基络合物，在一个19世纪被博物馆获得的人类木乃伊的案例中，揭示了这种木乃伊可能由纯沥青进行的古老修复。香脂和天然沥青中自由基和钒基卟啉的同相和异相EPR强度之间的线性相关性揭示了自由基和钒基卟啉络合物的纳米结构，该结构不受香脂制备的影响。这表明在古埃及历史沥青中顺磁性探针具有卓越的化学稳定性。

更新日期：2020-12-01

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南