Multi-Scale 3D Printing of Magnetic Polymer Nanocomposites with Controlled Particle Dispersion and Hyperthermic...

The ability to encode well-defined physical properties and spatiotemporally controlled responses into multifunctional nanocomposites is enabling a new generation of advanced responsive systems. We describe the synthesis of magnetic nanoflowers (NFs) and their full dispersion in PEG-based trimethylolpropane ethoxylate triacrylate (TET) to generate photo-curable nanocomposites. NF-loaded magnetic photocurable TET (Mol. Wt. 912 g mol^-1, NF-TET912) is shown to provide full particle dispersion and hence crosslinked polymers with full retention of the AC-field heating response. We demonstrate that these characteristics enable use of NF-TET912 for biomedical applications as a versatile coating on glass, metal and plastics and for multiple 2D and 3D manufacturing techniques including templating, direct light processing (DLP) and direct laser writing using 2 photon polymerization (2PP). Nanocomposite structures, achieved using DLP, have demonstrated good fidelity to design, and provide targeted (5°C) AC-field induced local temperature increases. Complex structures prepared using 2PP, have submicron feature size and resolution. The NF concentration range within which homogeneity and dispersion are possible is shown match the range needed for bio- applications and the materials exhibit no gross cellular toxicity. Finally, the potential of NF-TET912 for AC-field stimulated release of the antibiotic ciprofloxacin is evaluated.