Functional nanocomposites with graphene-DNA hybrid complexes: fabrication and surface properties under UV irradiation

Graphene-based nanocomposites with multifunctional properties are used as sensing materials in various environments. The integration of the graphene sensing elements into the polymer matrix is not a trivial task, as the overall sensing properties of the material are highly affected by the amount and homogeneity of the filler dispersion. Here we investigate the fabrication process of functional nanocomposite films based on graphene-DNA hybrid complexes embedded in a flexible polydimethylsiloxane (PDMS) matrix. UV-sensitive nanocomposites were realized exploiting the highly conductive nature of graphene nanoplatelets (GNP) combined with the chemical sensitivity of DNA strands to UV radiation. In addition, the DNA molecules are efficient solubilizing agents for the GNPs and, at the same time, enhance the curing process of the GNP-loaded PDMS matrix. Surface properties of the nanocomposite films in terms of morphology, electrical conductivity and wettability were investigated before and after UV-C exposure. Results give information on the potential applications of PDMS/GNP-DNA nanocomposites as biocompatible and sensitive materials for monitoring in extreme environments characterized by high levels of biologically-damaging UV-C radiation, such as the space environment