Polyoxometalate-encapsulated nanoparticles as antimicrobial materials for cultural heritage preservation

Abstract

Microorganisms are highly proficient at inhabiting and decaying paper, leather and stone objects, generating serious problems for the conservation of paintings, textiles and sculptures. The associated health risks coupled with the cost of decontaminating infected artefacts, exhibition rooms and depots make this a pertinent topic for museums, local authorities and private collectors alike. Moreover, our shared cultural heritage is a social, economic and environmental resource for Europe (Sterflinger and Piñar, 2013). Our aim is to engineer novel nanohybrid materials with enhanced antimicrobial properties that will act as biocidal agents to help prevent biodeterioration in objects of cultural heritage. Here we show how modular and highly processable hybrid materials can be constructed from the combination of three component parts: nanoparticles (NPs), polyoxometalates (POMs) and polymeric materials (De Matteis et al., 2014). The ability to tailor each of these three constituents offers a unique opportunity to produce precision biocides (e.g. laser-/photo-active nanomaterials) that meet the specific needs of cultural heritage conservation (e.g highly applicable colourless gels, waxes, sols etc.) (Herrmann et al). We propose a comprehensive antimicrobial functional screening programme to assess the activity of these materials against bacterial and fungal strains commonly found infecting objects of cultural heritage. Ultimately the most active and applicable nanohybrid candidates will be evaluated against biodeteriorative microorganism contaminants on paper, leather and stone surfaces in the laboratory (‘proof-of-concept’ surfaces) as well as in real cultural heritage objects from libraries and museums.