Combination of Magnetic Fluid Hyperthermia and Magneto-Mechanical Destruction: Particle characterisation, interaction study and in vitro testing

DANIELA P. VALDÉS; IRATI RODRIGO ARRIZABALAGA; MICHAEL STANTON; EMMA N. WELBOURNE; BORJA HERRERO DE LA PARTE; TEOBALDO E. TORRES; JOSÉ Á. GARCÍA; ROBERTO D. ZYSLER; FERNANDO PLAZAOLA; RUSSELL COWBURN

Conferencia; The 2020 Around-the-Clock Around-the-Globe Magnetics Conference; 2020

IEEE Magnetics Society

Magnetic hyperthermia and magneto-mechanical destruction are two emerging cancer therapies [1-2]. We studied the combination of these treatments to deve- lop a new and more efficient therapy. For hyperthermia, we synthesised magnetic iron-oxide nanoparticles (MIONs) with a diameter of 26 nm by the thermal decom- position of Fe(acac)3 [3] and coated with dextran in a post-synthesis procedure. Magnetic DC characterisation shielded that the MIONs are not completely super- paramagnetic at room temperature due to size distribution. Experimental specific power absorption (SPA) measurements were made in a custom-built AC magneto- meter resulting in SPA around 150 Wg-1 for a 0.5 mg ml-1 solution of MIONs in water (at 226 Oe and 301 kHz) as obtained from the area of the measured hysteresis loop times the frequency. For magneto-mechanical destruction, we fabricated synthetic antiferromagnetic microdiscs (MDs) with perpendicular anisotropy and diameter 2 um using a combination of sputtering and lithography techniques [4] and they were magnetically characterised using MOKE and VSM.Using an optical microscope with an integrated dipole electromagnet, we corro- borated the formation of linear arrangements due to interactions between MDs and the coated MIONs under DC fields from 30 to 3500 Oe and the magneto-mechanical response of MDs under low frequency magnetic fields.In rat colorectal cancer cell line CC531 incubated for 24 h with MDs and MIONs, we performed internalisation studies using TEM imaging and cytotoxicity experi- ments, finding that both MDs and coated MIONs are internalised and have minimal effects (