In this work an outlook on the design and application, in the cultural heritage field, of new tools for diagnostic and cleaning use, based on biocompatible hydrogels and electrochemical sensors, is reported. The use of hydrogels is intriguing because it does not require liquid treatment that could induce damage on artworks, while electrochemical biosensors not only are easy to prepare, but also can be selective for a specific compound and therefore are suitable for monitoring the cleaning process. In the field of restoration of paper artworks, more efforts have to be done in order to know how to perform the best way for an effective restoration. Rigid Gellan gel, made up of Gellan gum and calcium acetate, was proposed as a paper cleaning treatment, and selective biosensors for substances to be removed from this gel have been obtained by choosing the appropriate enzymes to be immobilized. Using this approach, it is possible to know when the cleanup process will be completed, avoiding lengthy and sometimes unnecessary cleaning material applications. 1. Introduction Paper is difficult to be restored, due to its fragility, its degradation process, and its multicomponent composition. The main paper component is cellulose, a polysaccharide made up of β-glucose units linked together by β(1 4) glycosidic bonds [1]. Structural changes due to ageing lead to a decrease in the stability of the material and in its strength and a change in color [2]. Critical steps, during restoring of paper material, are the cleaning of the sheets, the pH change, the optimization of the degree of humidity, and the glue removal. It is also very important that the time of the cleaning process is optimized in order to remove all pollution and degradation products and to minimize invasive treatment that can lead to irreversible damage. In the last year, the research in cultural heritage was focalized on the study of noninvasive diagnostic tools for the determination of paper artworks degradation [3]. Different techniques promise to be useful for cultural heritage applications, due to their specific properties. The combination of innovative and noninvasive material, such as an opportune hydrogel with selective electrochemical biosensors, gives the possibility to verify the degradation conditions of the paper artworks and to clean them efficiently, monitoring the removal process of pollution and degradation products. Electrochemical biosensors, based on enzyme, have been widely used in fields such as health care, food safety, and environmental monitoring. Health care is the main area in
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