Fe3O4–ZnO Core–Shell Nanoparticles Fabricated by Ultra-Thin Atomic Layer Deposition Technique as a Drug Delivery Vehicle

Fe 3 O 4 –ZnO nanoparticles with core–shell structures were successfully fabricated by an atomic layer deposition method. The core–shell NPs consisted of superparamagnetic Fe 3 O 4 cores of 100 nm average size and conformal ZnO shells of 10 nm thickness. The NPs showed a saturation magnetization of ~ 23 emu/g, which is suitable for magnetic delivery of the particles. Cytotoxicity testing revealed that the Fe 3 O 4 –ZnO NPs have high cell viability (over 90%) after 24 h culture. Also, they exhibited a high ibuprofen-loading capacity (640 μg per mg of the particles) and good release ability (> 90% after 72 h in simulated body fluid). As a result, the Fe 3 O 4 –ZnO nanoparticles with conformal ultra-thin ZnO shell layers are anticipated as promising drug delivery vehicles with acceptable cell viability and high drug loading-release abilities. Graphical Abstract