Effect of surface modification of graphene oxide with a reactive silane coupling agent on the mechanical properties and biocompatibility of acrylic bone cements

Abstract

Carbon allotrope materials (i.e. carbon nanotubes (CNTs), graphene, graphene oxide (GO)), have been used to reinforce acrylic bone cement. Nevertheless, the intrinsic incompatibility among the above materials produces a deficient interphase. Thus, in this work, the effect of the content of functionalized graphene oxide with a reactive silane on the mechanical properties and cell adhesion of acrylic bone cement was studied. GO was obtained by an oxidative process on natural graphite; subsequently, GO was functionalized with 3-methacryloxypropyltrimethoxysilane (MPS) to enhance the interphase between the graphenic material and acrylic polymeric matrix. Pristine GO and functionalized graphene oxide (GO-MPS) were characterized physicochemically (XPS, XRD, FTIR, and Raman) and morphologically (SEM and TEM). Silanized GO was added into the acrylic bone cement at different concentrations; the resulting materials were characterized mechanically, and their biocompatibility was also evaluated. The physicochemical characterization results showed that graphite was successfully oxidized, and the obtained GO was successfully functionalized with the silane coupling agent (MPS). SEM and TEM images showed that the GO is composed of few stacked layers. Compression testing results indicated a tendency of increasing stiffness and toughness of the acrylic bone cements at low concentration of functionalized GO. Additionally, the bending testing results showed a slightly increase in bone cement strain with the incorporation of GO-MPS. Finally, all samples exhibited cell viability higher than 70%, which means that materials are considered non-cytotoxic, according to the ISO 10993-5 standard.

Keywords:

• Graphene oxide
• acrylic bone cement
• silane functionalization
• mechanical properties
• cell viability

Acknowledgements

The authors would like to thank the collaboration of Santiago Duarte Arana for the technical support in morphological characterization, Raman studies and laboratory resources. Likewise, the authors would also like to thank Dra. Patricia Quintana Owen and Wilian Cauich for the support in XPS technique.

Disclosure statement

The authors declare that they have no financial or non-financial conflicts of interest related to this research.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.