Synthesis of Manganese Ferrite/Graphene Oxide Nanocomposites for Biomedical Applications

Abstract

In this study, MnFe(2)O(4) nanoparticle (MFNP)-decorated graphene oxide nanocomposites (MGONCs) are prepared through a simple mini-emulsion and solvent evaporation process. It is demonstrated that the loading of magnetic nanocrystals can be tuned by varying the ratio of graphene oxide/magnetic nanoparticles. On top of that, the hydrodynamic size range of the obtained nanocomposites can be optimized by varying the sonication time during the emulsion process. By fine-tuning the sonication time, MGONCs as small as 56.8 ± 1.1 nm, 55.0 ± 0.6 nm and 56.2 ± 0.4 nm loaded with 6 nm, 11 nm, and 14 nm MFNPs, respectively, are successfully fabricated. In order to improve the colloidal stability of MGONCs in physiological solutions (e.g., phosphate buffered saline or PBS solution), MGONCs are further conjugated with polyethylene glycol (PEG). Heating by exposing MGONCs samples to an alternating magnetic field (AMF) show that the obtained nanocomposites are efficient hyperthermia agents. At concentrations as low as 0.1 mg Fe mL(-1) and under an 59.99 kA m(-1) field, the highest specific absorption rate (SAR) recorded is 1588.83 W g(-1) for MGONCs loaded with 14 nm MFNPs. It is also demonstrated that MGONCs are promising as magnetic resonance imaging (MRI) T(2) contrast agents. A T(2) relaxivity value (r(2) ) as high as 256.2 (mM Fe)(-1) s(-1) could be achieved with MGONCs loaded with 14 nm MFNPs. The cytotoxicity results show that PEGylated MGONCs exhibit an excellent biocompatibility that is suitable for biomedical applications.

Enhanced magnetic anisotropy and heating efficiency in multi-functional manganese ferrite/graphene oxide nanostructures

“…1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 To elucidate the interaction of MnFe2O4 NPs with the functional groups on the surface of GO sheets, Fourier Transform Infrared (FTIR) spectra were recorded and analyzed. FTIR is a useful technique to confirm that the nanoparticles are anchored to GO surface, as has been shown by several groups 15,16 including ours 17 . Fig.…”

A Reusable Biomimetic Magnetic Nanoenzyme for Cellulosic Biomass Degradation

“…The X-ray diffractograms of MN and BMNE contained identical peaks, which indicates that the crystalline spinel ferrite core structure of the MN was retained following functionalization (Fig. S3) [38,39]. Furthermore, the BMNE consists of only 10 wt% of carboxylic derivative 1, as was determined from the results of TGA measurements (Fig.…”

Recent Advances in the Emulsion Solvent Evaporation Technique for the Preparation of Nanoparticles and Nanocapsules

“…Upon emulsification and evaporation of the organic phase, spherical aggregates of the nanocrystals are formed. This method has also recently been exploited to prepare manganese ferrite/graphene oxide nanocomposites [89] and siRNA-loaded magnetic metal nanoparticles [90]. Among different possible morphologies, capsules (i.e., core-shell particles with one liquid core) are often targeted morphologies for the protection and encapsulation of substances.…”