Au-Coated Ni80Fe20 Submicron Magnetic Nanodisks: Interactions With Tumor Cells

Abstract

Effective interaction and accumulation of nanoparticles (NPs) within tumor cells is crucial for NP-assisted diagnostic and therapeutic biomedical applications. In this context, the shape and size features of NPs can severely influence the strength of adhesion between NPs and cell and the NP internalization mechanisms. This study proved the ability of the PT45 and A549 tumor cells to uptake and retain magnetic Au-coated Ni 80 Fe 20 nanodisks (NDs) prepared by means of a bottom-up self-assembling nanolithography technique assisted by polystyrene nanospheres. The chosen geometrical parameters, i.e., diameter (≈650 nm) and thickness (≈30 nm), give rise to magnetic domain patterns arranged in vortex state at the magnetic remanence. PT45 and A549 cell lines were cultured in the presence of different concentrations of Au-coated Ni 80 Fe 20 nanodisks, and their biocompatibility was evaluated by viability and proliferation tests. Electron microscopy techniques and a combined CARS (Coherent Anti-stokes Raman Scattering) and TPL (two-photon photoluminescence) microscopy allow localizing and distinguishing the NDs within or attached to the tumor cells, without any labeling. A quantitative measurement of ND amount retained within tumor cells as a function of ND concentrations was performed by the Instrumental Neutron Activation Analysis (INAA) characterization technique.

From spectral analysis to hysteresis loops: a breakthrough in the optimization of magnetic nanomaterials for bioapplications

“…The last two decades have witnessed a boost of biomedical applications based on the unique properties of magnetic nanomaterials [1][2][3][4]. Magnetic single core [5] and multi-core nanoparticles [6], either bare [7] or submitted to surface functionalization [8,9], core-shell systems [10,11], supraparticles [12], hollow nanoparticles [13], nanochains [14,15] and nanodiscs [16,17] are being actively investigated in view of their application in modern therapies of precision medicine [18,19] as well as in radiation-free, non-invasive imaging or spectroscopy techniques and in the development of sensitive bionsensors [20][21][22]. A common feature of most of the above mentioned applications is that they typically make use of magnetic nanomaterials driven at high frequency in the non-linear magnetization regime [23] (the strictly linear magnetization regime, i.e.…”