title: Conformal cytocompatible ferrite coatings facilitate the realization of a nanovoyager in human blood.
abstract: Controlled motion of artificial nanomotors in biological environments, such as blood, can lead to fascinating biomedical applications, ranging from targeted drug delivery to microsurgery and many more. In spite of the various strategies used in fabricating and actuating nanomotors, practical issues related to fuel requirement, corrosion, and liquid viscosity have limited the motion of nanomotors to model systems such as water, serum, or biofluids diluted with toxic chemical fuels, such as hydrogen peroxide. As we demonstrate here, integrating conformal ferrite coatings with magnetic nanohelices offer a promising combination of functionalities for having controlled motion in practical biological fluids, such as chemical stability, cytocompatibility, and the generated thrust. These coatings were found to be stable in various biofluids, including human blood, even after overnight incubation, and did not have significant influence on the propulsion efficiency of the magnetically driven nanohelices, thereby facilitating the first successful "voyage" of artificial nanomotors in human blood. The motion of the "nanovoyager" was found to show interesting stick-slip dynamics, an effect originating in the colloidal jamming of blood cells in the plasma. The system of magnetic "nanovoyagers" was found to be cytocompatible with C2C12 mouse myoblast cells, as confirmed using MTT assay and fluorescence microscopy observations of cell morphology. Taken together, the results presented in this work establish the suitability of the "nanovoyager" with conformal ferrite coatings toward biomedical applications.
authors.affiliation: Centre for Nano Science and Engineering, ‡Materials Research Centre, §Department of Electrical Communication Engineering, ⊥Department of Physics, Indian Institute of Science , Bangalore 560012, India.
authors.forename: Pooyath Lekshmy
authors.initials: PL
authors.lastname: Venugopalan
authors.forename: Ranajit
authors.initials: R
authors.lastname: Sai
authors.forename: Yashoda
authors.initials: Y
authors.lastname: Chandorkar
authors.forename: Bikramjit
authors.initials: B
authors.lastname: Basu
authors.forename: Srinivasrao
authors.initials: S
authors.lastname: Shivashankar
authors.forename: Ambarish
authors.initials: A
authors.lastname: Ghosh
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry* / Q000378:metabolism; D005290:Ferric Compounds / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008422:Materials Testing; D051379:Mice; D009038:Motion
chemical_list: D020099:Coated Materials, Biocompatible; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; C001215:ferrite