Surface analysis of ancient parchments via the EVA film: The Aleppo Codex

The margins of several pages of the Aleppo codex have been found to be corroded and contaminated by diffuse maculae. In order to understand the origin of this decay these margins have been analysed by applying EVA (ethylene vinyl acetate plastic embedded with strong cation and anion exchangers and mixed with C₈ and C₁₈ hydrophobic resins) diskettes for harvesting surface material. The captured compounds have been eluted, digested with trypsin and analysed by nano-HPLC-MS. Three major strains of Aspergillus have been identified, namely Aspergillus fumigatus, Aspergillus pseudoglaucus, Aspergillus amstelodami, together with a lactobacillus strain and human keratins. The novelty of this investigation is that for the first time the EVA technology has been applied to ancient parchments in the absence of mechanical deformation or distortion that could be induced if there had been water exchange between the EVA diskettes and the parchment. These findings should help curators to find suitable restoration protocols for these precious documents belonging to the world Cultural Heritage.