Graphene Oxide as a Multifunctional Platform for Intracellular Delivery, Imaging, and Cancer Sensing

Abstract

Graphene oxide (GO), the most common derivative of graphene, is an exceptional nanomaterial that possesses multiple physical properties critical for biomedical applications. GO exhibits pH-dependent fluorescence emission in the visible/near-infrared, providing a possibility of molecular imaging and pH-sensing. It is also water soluble and has a substantial platform for functionalization, allowing for the delivery of multiple therapeutics. GO physical properties are modified to enhance cellular internalization, producing fluorescent nanoflakes with low (<15%) cytotoxicity at the imaging concentrations of 15 μg/mL. As a result, at lower flake sizes GO rapidly internalizes into HeLa cells with the following 70% fluorescence based clearance at 24 h, assessed by its characteristic emission in red/near-IR. pH-dependence of GO emission is utilized to provide the sensing of acidic extracellular environments of cancer cells. The results demonstrate diminishing green/red (550/630 nm) fluorescence intensity ratios for HeLa and MCF-7 cancer cells in comparison to HEK-293 healthy cells suggesting a potential use of GO as a non-invasive optical sensor for cancer microenvironments. The results of this work demonstrate the potential of GO as a novel multifunctional platform for therapeutic delivery, biological imaging and cancer sensing.

Self-Assembly of Organic Nanomaterials and Biomaterials: The Bottom-Up Approach for Functional Nanostructures Formation and Advanced Applications

“…Due to their special physico-chemical characteristics and electronic properties, the graphene can yield various applications, including batteries, light emitting diodes and supercapacitors [220,221]. Moreover, biomedical applications of graphene include bio-medical imaging and anticancer drug delivery [222,223]. Recently, graphene oxide (GO) nanocarriers functionalized with lactosylated chitosan oligosaccharide was constructed for the targeted drug delivery of doxorubicin drug and DNA sequences into the (human) hepatic carcinoma cells (QGY-7703) [223].…”

Graphenic Materials for Biomedical Applications

“…The ability of GO to change its fluorescence at visible/NIR wavelengths as a function of pH was applied to scan cancerous tissues. For example, Campbell et al described this type of DDS as a new multifunctional agent for the delivery, imaging, and detection of tumor environments [140]. GO is able to detect the acidic extracellular tumor environments of the HeLa and MCF-7 cells in comparison with non-cancer HEK-293 cells, and possesses excellent characteristics, such as its chemical and optical properties, easy functionalization, large surface area, high thermal stability, suitable conductivity, and larger range of biomedical applications [6].…”

“…GO is able to detect the acidic extracellular tumor environments of the HeLa and MCF-7 cells in comparison with non-cancer HEK-293 cells, and possesses excellent characteristics, such as its chemical and optical properties, easy functionalization, large surface area, high thermal stability, suitable conductivity, and larger range of biomedical applications [6]. In addition to detection, GO can protect gene therapeutics from nuclease degradation and streamline treatment by increasing intracellular drug delivery that can be covalently or non-covalently associated with various functionalization approaches [140]. For example, hybrid miRNA provides GO with positive functional groups that could take superiority over targeting and PTT when suppressing cancer cells [27].…”

Development of hydrophobic reduced graphene oxide as a new efficient approach for photochemotherapy

“…Recently, nanoparticles with functionalised carbon family networks have shown great promise for cancer targeting and drug delivery in specic chemotherapy treatments, such as carbon dots, carbon nanotubes (CNTs), fullerenes, and graphene materials. [11][12][13][14][15][16] Among these carbon nanomaterials, graphene is the most suitable and commonly used material in a variety of applications due to its sheet exibility. It is capable of generating heat by alternating the magnetic eld or through lasers of noble metals.…”