Graphene oxide (GO)-based nanocarriers have been frequently studied due to their high drug loading capacity. However, the unsatisfactory biocompatibility of these GO-based nanocarriers hampers their use in clinical settings. This review discusses how each of the physicochemical characteristics (e.g., size, surface area, surface properties, number of layers and particulate states) and surface coatings on GO affect its in vitro and in vivo nanotoxicity. We provide an overview on the effect of GO properties on interactions with cells such as red blood cells, macrophages and cell lines, and experimental organisms including rodents, rabbits and Zebrafish, offering some guidelines for development of safe GO-based nanocarriers. We conclude the paper by outlining the challenges involving GO-based formulations and future perspectives of this research in the biomedical field.
We synthesized a dextrin (DEX)-conjugated graphene oxide (GO) nanocarrier (GO100-DEX) as a potential drug delivery system to respond to a tumor-associated stimulus, α-amylase, that has high permeability through the fenestrated endothelial barrier to the tumor site. At acidic pH and in the presence of α-amylase to simulate tumor conditions, GO100-DEX released a 1.5-fold higher amount of doxorubicin (DOX) than of GO100. Under the same conditions, the cytotoxic effects of GO100-DEX/DOX were 2-fold greater than those of free DOX and 2.9-fold greater than those of GO100/DOX. Employing an in vitro biomimetic microfluidic blood vessel model lined with human umbilical vein endothelial cells, we evaluated the tumor vasculature endothelial permeation of GO100-DEX and GO100 using dextrans of 10 and 70kDa for comparison and as standards to validate the microfluidic blood vessel model. The results showed that the permeabilities of GO100-DEX and GO100 were 4.3- and 4.9-fold greater than that of 70kDa dextran and 2.7- and 3.1-fold higher than that of 10kDa dextran, thus demonstrating the good permeability of the GO-based nanocarrier through the fenestrated endothelial barrier.
Green synthesis approaches are gaining significance as promising routes for the sustainable preparation of nanoparticles, offering reduced toxicity towards living organisms and the environment. Nanomaterials produced by green synthesis approaches can offer additional benefits, including reduced energy inputs and lower production costs than traditional synthesis, which bodes well for commercial-scale production. The biomolecules and phytochemicals extracted from microbes and plants, respectively, are active compounds that function as reducing and stabilizing agents for the green synthesis of nanoparticles. Microorganisms, such as bacteria, yeasts, fungi, and algae, have been used in nanomaterials' biological synthesis for some time. Furthermore, the use of plants or plant extracts for metal and metal-based hybrid nanoparticle synthesis represents a novel green synthesis approach that has attracted significant research interest. This review discusses various biosynthesis approaches via microbes and plants for the green preparation of metal and metal oxide nanoparticles and provides insights into the molecular aspects of the synthesis mechanisms and biomedical applications. The use of agriculture waste as a potential bioresource for nanoparticle synthesis and biomedical applications of biosynthesized nanoparticles is also discussed.
In this study, nanohybrid materials consisting of graphene oxide (GO), β‑cyclodextrin (CD) and poly(amido amine) dendrimer (DEN) were successfully prepared by covalent bonding. GO-CD and GO-CD-DEN were found to be potential nanocarriers for anticancer drugs including chemotherapeutics (doxorubicin (DOX), camptothecin (CPT)) and photosensitizer (protoporphyrin IX (PpIX)). GO-CD possessed 1.2 times higher DOX-loading capacity than GO due to inclusion of additional DOX to the CD. The drug loading on GO-CD-DEN increased in the order: DOX