Formation of hydrated PEG layers on magnetic iron oxide nanoflowers shows internal magnetisation dynamics and generates high in-vivo efficacy for MRI and magnetic hyperthermia

Modulation of hyperthermic and relaxometric responses of magnetic iron oxide nanoparticles through ligand exchange provides design criteria for dual-functionality

“…The particle characterisation and hyperthermic and relaxivity data for greater than the value of 23 nm measured for OA/OAm-MNPs in toluene, due the grafted PEG2000 chains. 49,53 The relatively small size and low PDI of 0.09 suggest full particle dispersion. The hyperthermic response of the aqueous P-MNP suspensions is significantly reduced to 245 W g -1 , Figure 4B, far lower than 1000 and 910 W g -1 measured for dispersed OA/OAm-and OA-MNPs, respectively, in toluene.…”

“…Hence in situ PEG2000-gallol surface grafting was undertaken before work-up of an OA/OAm-MNP batch. This functionalised PEG has been recently reported, 53 and full details of the procedure are provided in the Experimental section. The typical Fe yield for the in situ reaction was B40% (B45% for OA/OAm-MNPs).…”

Emerging Magnetic Fabrication Technologies Provide Controllable Hierarchically‐Structured Biomaterials and Stimulus Response for Biomedical Applications

“…[ 68 ] However it is usually possible to produce sufficient temperature increases at reasonable concentrations for many biomedical driven applications, including in vivo tumor eradication or controlled release platforms. [ 23 , 69 ] In Section 3.7 we also describe an example of extrusion 3D‐printed Mag‐Gels for in vivo combined hyperthermic tumor eradication and tissue repair.…”

“…In our previous work in this field, we demonstrated 3D printable responsive magnetic hydrogels composed of magnetic iron‐oxide nanoflowers and Pluronic polymers that upon AC‐field irradiation (642 kHz, 16 mT) provided localized spatiotemporally‐specified heating. [ 69 ] The temperature jumps achieved were sufficient to increase the diffusion of methylene blue, which was released from the patterned grids. [ 69 ] More recently we further demonstrated that the heating capabilities of such grids can be enhanced by modulation of inter‐MNP interactions (preventing formulation‐induced aggregation which suppresses hyperthermia) by addition of graphene oxide flakes as spacers.…”

“…[ 69 ] The temperature jumps achieved were sufficient to increase the diffusion of methylene blue, which was released from the patterned grids. [ 69 ] More recently we further demonstrated that the heating capabilities of such grids can be enhanced by modulation of inter‐MNP interactions (preventing formulation‐induced aggregation which suppresses hyperthermia) by addition of graphene oxide flakes as spacers. [ 23 ] The improved responses provide possibilities for patterned and directional hyperthermic release.…”