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 Fe 3 O 4 -GO in the form of nanospheres with a core−shell structure (∼50 nm). The ultrasonic complexation occurs via the Hbond formation with the ibuprofen side chains (CH, CH 2 , and CH 3 ) and C−O−H involving the interaction of carboxylic groups and Fe−O bonds. Synthesized ibuprofen-Fe 3 O 4 -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-Fe 3 O 4 -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 CHO 2 + , 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 Fe 3 O 4 and GO in two basic fundamental COX-independent mechanisms.