Evaluation of the irradiation treatment effects on ancient parchment samples

In this work, the effect of X-ray irradiation as a disinfection treatment in original ancient parchment samples, belonging to a discarded book cover of a 16th-century archival register, has been evaluated. Specifically, the bacterial and fungal species isolated from the book cover have been characterized and then irradiated with increasing doses of X-rays with the aim to evaluate the effectiveness of the antimicrobial protocol on the isolated microorganisms. The deterioration effects induced by the X-ray treatment as well as the natural aging on the collagen matrix of the parchment sample have been tested by employing several techniques, namely, Light Transmission Analysis, Fiber Optic Reflectance Spectroscopy, Attenuated Total Reflectance-Fourier Transformed Infrared spectroscopy, UV Resonant Raman spectroscopy and Atomic Force Microscopy. The results reveal that the irradiation treatment applied to our ancient parchment samples deteriorated by biological attack and other naturally occurring phenomena, possibly associated with inappropriate conservation conditions, does not seem to induce further damage factors even when large doses of irradiation are employed. The X-rays-based disinfection treatment effects are limited on the collagen support and this confirms the potential of this method in mass disinfection of library and archival materials.