Developing the next generation of graphene-based platforms for cancer therapeutics: The potential role of reactive oxygen species

Abstract

Graphene has a promising future in applications such as disease diagnosis, cancer therapy, drug/gene delivery, bio-imaging and antibacterial approaches owing to graphene's unique physical, chemical and mechanical properties alongside minimal toxicity to normal cells, and photo-stability. However, these unique features and bioavailability of graphene are fraught with uncertainties and concerns for environmental and occupational exposure. Changes in the physicochemical properties of graphene affect biological responses including reactive oxygen species (ROS) production. Lower production of ROS by currently available theranostic agents, e.g. magnetic nanoparticles, carbon nanotubes, gold nanostructures or polymeric nanoparticles, restricts their clinical application in cancer therapy. Oxidative stress induced by graphene accumulated in living organs is due to acellular factors which may affect physiological interactions between graphene and target tissues and cells. Acellular factors include particle size, shape, surface charge, surface containing functional groups, and light activation. Cellular responses such as mitochondrial respiration, graphene-cell interactions and pH of the medium are also determinants of ROS production. The mechanisms of ROS production by graphene and the role of ROS for cancer treatment, are poorly understood. The aim of this review is to set the theoretical basis for further research in developing graphene-based theranostic platforms.

Biocompatibility and Toxicity of Graphene Quantum Dots for Potential Application in Photodynamic Therapy

“…Recent advances in the GQD field have provided unique optical properties, plus remotely controlled release of therapeutic agents in vitro and in vivo [25,26,62] . controlling the biological activities of these QDs [9,28,63,64] . In general, several synthesis techniques are available and have been widely used for the preparation of GQDs, such as lithography [65,66] , hydrothermal cutting [65,66] and electrochemical preparation [67] .…”

“…These highly reactive species result in a shift of redox balance and trigger the activation of transcription factors implicated in the initiation of cell death signalling via apoptosis and/or necrosis. The efficacy of PDT mainly relies on the yield of singlet oxygen and other ROS production by a PS and this yield depends on the nature of PS involved [9,10] .…”

Nanoparticles as Tools to Target Redox Homeostasis in Cancer Cells

“…Nanomedicine is based on the use of synthetic particles of 1-1000 nm diameter (nanoparticles, NPs), which can be classified into six main groups: carbon NPs, metal NPs, ceramic NPs, semiconductor NPs, polymeric NPs and lipid-based NPs [14]. In particular, carbon NPs employ the different allotropic forms of carbon, including caged structures (e.g., fullerenes), tubular structures (e.g., carbon nanotubes (CNTs), sheet structures (e.g., graphene and nanodots) [15,16].…”

Hydrophilic Carbon Nanomaterials: Characterisation by Physical, Chemical, and Biological Assays

“…The development of carbon nanomaterials has presented new opportunities for disease diagnosis and therapies with impact on human healthcare. In the field of diagnostics, carbon nanomaterials have performed roles in imaging and sensing, whereas their development as novel therapies has arisen mainly from their ability to support efficient drug/gene delivery systems and to promote the generation of reactive oxygen species (ROS) upon irradiation with light (e.g., cancer phototherapy) . Despite the benefits that carbon nanomaterials can provide to medicine, their intrinsic therapeutic potential, coming from their antioxidant and radical scavenging capabilities in biological systems, has not been extensively investigated.…”

“…In the field of diagnostics, carbon nanomaterials have performed rolesi ni maging [1] and sensing, [2,3] whereas their development as novel therapies has arisen mainly from their ability to support efficient drug/gened elivery systems [4,5] and to promote the generation of reactive oxygen species (ROS) upon irradiation with light (e.g.,c ancer phototherapy). [6][7][8] Despite the benefits that carbon nanomaterials can provide to medicine, their intrinsic therapeutic potential, comingf rom their antioxidant and radical scavenging capabilities in biological systems, has not been extensively investigated. The antioxidant properties of carbon-basedm aterials, such as carbon nanotubes, graphene and graphene oxide, have been broadly recognised, [9][10][11][12][13] although they have only found utility for the protection of polymericm atrices against oxidative degradation, [14][15][16][17] and not in the biomedical field due to their toxicity and low bioavailability.…”