ORIGINAL PAPER Behavior of cellobiose in iron-containing solutions: towards a better understanding of the dominant mechanism of degradation of cellulosic paper by iron gall inks Alice Gimat . Anne-Laurence Dupont . He ´le `ne Lauron-Pernot . Sabrina Paris . Ve ´ronique Rouchon . Pascale Massiani Received: 4 April 2017 / Accepted: 2 August 2017 Ó Springer Science+Business Media B.V. 2017 Abstract Cellobiose, a dimer of glucose wearing a glycosidic bond as in cellulose, was used as model molecule to understand the chemical degradation pathways taking place in iron gall inks impregnated papers. Experiments were carried out in liquid phase at 80 °C to study the effects of pH and of the presence of iron and oxygen on the cleavage of the glycosidic bond. Capillary electrophoresis was used to quantita- tively follow the cellobiose degradation and the formation of glucose. Attenuated total reflectance infrared spectroscopy of freeze-dried samples was done to identify the presence of secondary products of reaction. UV–Visible spectroscopy allowed monitor- ing the iron(II) and iron(III) contents as a function of time and pH. The data reveal that the simultaneous presence of iron and oxygen enhances the degradation of cellobiose. Nevertheless, even if some oxidation of the sugar molecules occurs, the predominant pathway of cellobiose decomposition is found to be acid- catalyzed hydrolysis due to the high acidity of the medium generated from the oxidation and precipita- tion of iron. Keywords Cellobiose Á Paper corrosion Á Iron gall ink Á pH Á Oxidation Á Acid-catalyzed hydrolysis Introduction Iron gall inks (IGIs) are made of gall nut extracts (rich in gallic acid) and iron(II) salts (such as iron(II) sulphate). In the presence of oxygen, the mixture of these two components produces a dark iron(III)/tannin precipitate characteristic of the ink color (Krekel 1999; Wunderlich et al. 1991; Ponce et al. 2016). Gum Arabic is usually added as a binder. Under certain conditions, IGIs can significantly damage the cellu- losic paper substrate on which they are deposited, causing browning and loss of mechanical properties (Reissland 2000). This degradation proceeds first by diffusion of ink components around the ink lines (usually under high humidity conditions), followed by chemical reactions provoking paper browning and embrittlement. Paper degradation has motivated numerous mech- anistic studies. It is currently attributed to concurrence between acid-catalyzed hydrolysis and oxidation pathways, both provoking chain scissions (Kolar and Strilic 2006). In acidic medium, it is usually admitted A. Gimat Á A.-L. Dupont Á S. Paris Á V. Rouchon Centre de Recherche sur la Conservation (CRC, USR 3224), Sorbonne Universite ´s, Muse ´um National d’Histoire Naturelle, Ministe `re de la Culture et de la Communication, CNRS, CP21, 36 rue Geoffroy-Saint- Hilaire, 75005 Paris, France A. Gimat Á H. Lauron-Pernot Á P. Massiani (&) Laboratoire de Re ´activite ´ de Surface (LRS), Sorbonne Universite ´s, UPMC Univ Paris 06, CNRS, UMR 7197, 4 Place Jussieu, 75005 Paris, France e-mail: pascale.massiani@upmc.fr 123 Cellulose DOI 10.1007/s10570-017-1434-3