Graphene-encapsulated magnetic nanoparticles for safe and steady delivery of ferulic acid in diabetic mice

Iron nanoparticles encapsulated within graphene shells (Fe@C) were examined for cellular internalization, subcellular behavior, biocompatibility, and influence on cell viability and proliferation. Studies on human lung (adenocarcinoma human alveolar basal epithelial) and skin (epidermoid carcinoma) cells indicate Fe@C is less toxic and more biocompatible than the magnetite nanoparticles coated by an amorphous carbon (Fe3O4@C). Fe3O4@C exhibited more signs of degradation than Fe@C when exposed to murine macrophages (mouse monocyte-macrophages J774). Unlike Fe3O4@C, Fe@C has a high drug loading capacity (0.18 g/g) for ferulic acid, an active pharmaceutical ingredient found in the traditional Chinese herb Angelica sinensis and releases the drug at a constant dosing rate of 8.75 mg/g/day over 30 days. Ferulic acid released by Fe@C injected subcutaneously in diabetic BALB/c mice is effective in lowering the blood glucose level.