Engineered Highly Porous Polyvinyl Alcohol Hydrogels with Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and Graphene Nanosheets for Musculoskeletal Tissue Engineering: Morphology, Water Sorption, Thermal, Mechanical, Electrical Properties, and Biocompatibility.

Electroactive composite materials are very promising for musculoskeletal tissue engineering because they can be applied in combination with electrostimulation. In this context, novel graphene-based poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/polyvinyl alcohol (PHBV/PVA) semi-interpenetrated networks (semi-IPN) hydrogels were engineered with low amounts of graphene (G) nanosheets dispersed within the polymer matrix to endow them with electroactive properties. The nanohybrid hydrogels, obtained by applying a hybrid solvent casting-freeze-drying method, show an interconnected porous structure and a high water-absorption capacity (swelling degree > 1200%).

Pro-Myogenic Environment Promoted by the Synergistic Effect of Conductive Polymer Nanocomposites Combined with Extracellular Zinc Ions.

A new strategy based on the combination of electrically conductive polymer nanocomposites and extracellular Zn ions as a myogenic factor was developed to assess its ability to synergically stimulate myogenic cell response. The conductive nanocomposite was prepared with a polymeric matrix and a small amount of graphene (G) nanosheets (0.7% /) as conductive filler to produce an electrically conductive surface.

Engineering alginate hydrogel films with poly(3-hydroxybutyrate-co-3-valerate) and graphene nanoplatelets: Enhancement of antiviral activity, cell adhesion and electroactive properties.

A new biodegradable semi-interpenetrated polymer network (semi-IPN) of two US Food and Drug Administration approved materials, poly(3-hydroxybutyrate-co-3-valerate) (PHBV) and calcium alginate (CA) was engineered to provide an alternative strategy to enhance the poor adhesion properties of CA. The synthesis procedure allows the additional incorporation of 10 % w/w of graphene nanoplatelets (GNPs), which have no cytotoxic effect on human keratinocytes. This quantity of multilayer graphene provides superior antiviral activity to the novel semi-IPN against a surrogate virus of SARS-CoV-2.

Graphene Oxide versus Carbon Nanofibers in Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Films: Degradation in Simulated Intestinal Environments.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a microbial biodegradable polymer with a broad range of promising industrial applications. The effect of incorporation of low amounts (1% ) of carbon nanomaterials (CBNs) such as 1D carbon nanofibers (CNFs) or 2D graphene oxide (GO) nanosheets into the PHBV polymer matrix affects its degradation properties, as it is reported here for the first time. The study was performed in simulated gut conditions using two different media: an acidic aqueous medium (pH 6) and Gifu anaerobic medium.

Novel Semi-Interpenetrated Polymer Networks of Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate)/Poly (Vinyl Alcohol) with Incorporated Conductive Polypyrrole Nanoparticles.

This paper reports the preparation and characterization of semi-interpenetrating polymer networks (semi-IPN) of poly(3-hydroxybutirate-co-3-hydroxyvalerate), PHBV, and poly (vinyl alcohol), PVA, with conductive polypirrole (PPy) nanoparticles. Stable hybrid semi-IPN (PHBV/PVA 30/70 ratio) hydrogels were produced by solvent casting, dissolving each polymer in chloroform and 1-methyl-2-pyrrolidone respectively, and subsequent glutaraldehyde crosslinking of the PVA chains. The microstructure and physical properties of this novel polymeric system were analysed, including thermal behaviour and degradation, water sorption, wettability and electrical conductivity.