ИСТИНА

In this work, we prepare pairwise connected Fe3O4 − Au hybrid nanoparticles (NPs) with diameters of 6-44 nm Fe3O4 and 3-11 nm Au aiming for optimized theranostics response in magnetic particle hyperthermia (MPH) and magnetic resonance imaging (MRI). With increasing NPs diameter from 6 to 25 nm in agarose mimicking tissues, the MPH reveal that the specific loss power increases from 12 to 327 W*gFe−1, while for the MRI, we observe the growth of the r2-relaxivity from 118 to 612 mM−1s−1. The 25 nm and 44 nm diameter NPs show the similar theranostic performance. These values are significantly enhanced in comparison to other Fe3O4 − Au hybrids due to their octahedral shape and large M𝑠. As a practical application, MRI-controlled drug delivery and dual-mode MRI/fluorescent imaging are presented for the optimized NPs size of 25 nm.