Fenton-Hydroxyl Radical Antioxidant Efficiency of Ibuprofen-Fe3O4-GO Nanospheres

Abstract

A feasible one-step “solvent-antisolvent” oil-free acoustic emulsification method is demonstrated for the complexation of pristine ibuprofen with Fe3O4-GO in the form of nanospheres with a core−shell structure (∼50 nm). The ultrasonic complexation occurs via the H- bond formation with the ibuprofen side chains (CH, CH2, and CH3) and C−O−H involving the interaction of carboxylic groups and Fe−O bonds. Synthesized ibuprofen-Fe3O4-GO nanospheres are efficient antioxidants with hydroxyl radical (·OH) scavenging and iron inactivation properties in the electro-Fenton process exhibiting ∼24 times higher diminishing rate than free ibuprofen per se and ∼161 times higher than pristine ibuprofen nanoparticles in aqueous medium. This pronounced antioxidant efficiency of ibuprofen-Fe3O4-GO nanospheres is due to the increased concentration of inactive protonated Fe(II) centers in Fe−O, C−Fe, and CO−Fe bonds (FeO+, CFe+, and COFe+) of complexed drug molecules and increased concentration of CHO2 +, OH+, and CO+ ions on the surface of nanospheres. The demonstrated method discloses the conditions of enhanced antioxidant efficiency of ibuprofen and defines the roles of Fe3O4 and GO in two basic fundamental COX-independent mechanisms.