Antioxidant Iron Oxide Nanoparticles: Their Biocompatibility and Bioactive Properties

A lot of nanomaterials have been applied to various nano-biotechnological fields, such as contrast agents, drug or gene delivery systems, cosmetics, and so on. Despite the expanding usage of nanomaterials, concerns persist regarding their potential toxicity. To address this issue, many scientists have tried to develop biocompatible nanomaterials containing phytochemicals as a promising solution. In this study, we synthesized biocompatible nanomaterials by using gallic acid (GA), which is a phytochemical, and coating it onto the surface of iron oxide nanoparticles (IONPs). Importantly, the GA-modified iron oxide nanoparticles (GA-IONPs) were successfully prepared through environmentally friendly methods, avoiding the use of harmful reagents and extreme conditions. The presence of GA on the surface of IONPs improved their stability and bioactive properties. In addition, cell viability assays proved that GA-IONPs possessed excellent biocompatibility in human dermal papilla cells (HDPCs). Additionally, GA-IONPs showed antioxidant activity, which reduced intracellular reactive oxygen species (ROS) levels in an oxidative stress model induced by hydrogen peroxide (H₂O₂). To investigate the impact of GA-IONPs on exosome secretions from oxidative stress-induced cells, we analyzed the number and characteristics of exosomes in the culture media of HDPCs after H₂O₂ stimulation or GA-IONP treatment. Our analysis revealed that both the number and proportions of tetraspanins (CD9, CD81, and CD63) in exosomes were similar in the control group and the GA-IONP-treated groups. In contrast, exosome secretion was increased, and the proportion of tetraspanin was changed in the H₂O₂-treated group compared to the control group. It demonstrated that treatment with GA-IONPs effectively attenuated exosome secretion induced by H₂O₂-induced oxidative stress. Therefore, this GA-IONP exhibited outstanding promise for applications in the field of nanobiotechnology.