Preparation and Characterization of Amine- and Carboxylic Acid-functionalized Superparamagnetic Iron Oxide Nanoparticles Through a One-step Facile Electrosynthesis Method

Abstract

Background: Surface modified magnetite nanoparticles (MNPs), can act as interesting candidates for use in various biomedical areas. Coating MNPs with amino- or carboxylic acidfunctionalized groups can be used as a tool for covalently binding MNPs to biomolecules for medical uses. The conventionally used methods are also mostly multistep routes requiring purification processes. Objective: Herein, we developed a simple and facile approach with potentials for the large-scale synthesis of bare and/or amine- and carboxylic acid-functionalized MNPs. The resulting product and similarly prepared bare MNPs were studied by XRD, FT-IR, DSC-TGA, TEM, FE-SEM, DLS and VSM analyses. Method: The magnetite NPs were deposited on the steel cathode by a cathodic electrochemical deposition procedure. A galvanostatic mode was applied in the electrodeposition experiments at a dc current density for 30 min. The purification steps were done for the prepared samples. The obtained black powders were evaluated by characterization analyses. Results: The XRD peaks are well-matched with a cubic spinel structure of magnetite and confirmed that the amino acid binding process did not result in a phase change in Fe3O4 during the electrodeposition. The presence of amine and carboxylic functional groups on the surface of the electrosynthesized MNPs was confirmed by FTIR. The size increases complicated the presence of the amino acid layer on the iron oxide nanoparticles as compared with bare MNPs. Conclusion: We synthesized amine- and carboxylic acid-functionalized magnetite NPs through facile novel method, and compare with the deposited bare MNPs. Our findings confirmed that the aspartic acid and asparagine can be efficiently coated on the surface of MNPs during their CE electrodeposition. The functionalized MNPs were found to have favorable size and proper magnetic properties which are suitable for biomedical applications.