AN APPLICATION OF MALDI-TOF MASS SPECTROMETRY FOR THE STUDY OF GUM-BASED BINDER POLYCHROMY FROM ANCIENT EGYPTIAN ARCHAEOLOGICAL OBJECTS
Type de document : Archive ouverte
| 39TH FRENCH DAYS OF MASS SPECTROMETRY
Auteur(s) : Eskenazi, Nicolas | Demey-Thomas, Emmanuelle | Mavrogianni, Theodora | Lattuati-Derieux, Agnes | Vinh, Joelle
Edité par HAL CCSD
- Type de document
- info:eu-repo/semantics/conferenceObject ; Conference poster
- Langue
- en
- Date de publication
- 2023-09-05
- Résumé
- International audience.
Investigating the chemical composition of historical objects offers invaluable insights into ancient civilizations’ techniques, materials, recipes, trade routes and practices, proving crucial for historians and curators. However, these approaches often come with challenges, notably the complex nature of ancient handmade materials and the preservation of sensitive archaeological objects. Ancient paintings often used plant gums (exudates) as binders, with gums such as arabic, tragacanth, cherry, and locust bean used for their individual properties, cultural preference, or geographic availability. While not directly encoded in DNA, like proteins, these polysaccharide gums have distinct monosaccharide compositions depending on their species of origin.In order to minimize samplings on these precious artifacts, we adapted a plant gum preparation method by Granzotto et al.(1) to suit our aminoquinoline liquid-matrix fingerprinting protocol for polysaccharides by MALDI-TOF mass spectrometry. The samples were wetted with alcohol and resolubilized in water using probe sonication. Subsequently, they were digested with a cocktail of two glycosidases, exo-β-1,3-galactanase (C. thermocellum) and endo-1,4-β-mannanase (C. japonicus). The MALDI matrix was prepared using 3-Aminoquinoline solubilized at 20 mg/mL in ammonium dihydrogen phosphate and acidified with para-Coumaric Acid. Finally, polysaccharide digests were spotted with the liquid matrix and analyzed using an AB Sciex 5800TOF/TOF instrument. These steps mitigate the degradation of such complex carbohydrates and maximize their detection and fragmentation in MS(/MS). Optimizing the method on reference modern gums from Acacia, Astragalus, Ceratonia and Prunus genera allowed us to detect and identify previously undocumented diagnostic oligosaccharides for those species, improving the screening method.We are applying these protocols to coffins’ paintings from Ancient Egypt in an attempt to better decrypt this precious piece of Human History and Ancient Egyptian culture.
- Citer la référence
- Eskenazi, Nicolas , Demey-Thomas, Emmanuelle , Mavrogianni, Theodora , Lattuati-Derieux, Agnes , Vinh, Joelle, AN APPLICATION OF MALDI-TOF MASS SPECTROMETRY FOR THE STUDY OF GUM-BASED BINDER POLYCHROMY FROM ANCIENT EGYPTIAN ARCHAEOLOGICAL OBJECTS, HAL CCSD,
