Graphene–Metal Oxide Composite Materials for Biomedical Applications

Over the past decade, owing to their highly enriched physiochemical properties, graphene-based metal oxide composites have been explored for various applications in the medical field. Due to its high surface area, easy functionalization, and ability to penetrate cell-membranes, graphene is becoming a promising candidate for bio-delivery carriers. Additionally, graphene-based materials are reported to be suitable carriers to overcome the disadvantages associated with conventional drug formulation. Moreover, various metals and their oxides could be coupled with graphene to form graphene–metal oxide composites. Due to excellent biocompatibility, solubility and selectivity, these composites show huge potential for bioimaging and diagnostic purposes. Metal coordination with graphene has also been found to enhance the antimicrobial activity against various human pathogens. A comprehensive review of developments of graphene-based metal oxide materials for biomedicine is missing in the literature. To address this, here we have presented a detailed review of material design, drug loading, release or diffusion kinetics, in vitro and in vivo applications, and device fabrication with graphene-based metal oxide materials. Recommendations for future research have been discussed with reference to related areas to better understand the underlying science and to develop better delivery, imaging, and sensing methods using graphene-based metal oxide composites.