Multimodal Hybrid FePt/SiO2/Au Nanoparticles for Nanomedical Applications: Combining Photothermal Stimulation and Manipulation With an External Magnetic Field

Despite the increasing number of successful treatments for cancer, new forms of therapy are urgently required in order to combat the disease. In this investigation, we have produced an innovative material based on FePt/SiO2/Au hybrid nanoparticles that exhibit a combination of photothermal and magnetic properties as a basis for a local hypothermia treatment. The magnetic cores of FePt exhibit the superparamagnetic properties necessary for biomedical purposes, while the gold nanoshells absorb light in the near-infrared range, because of their semicontinuous nature and the nanoparticle clustering, as predicted by our modeling. The as-prepared hybrid FePt/SiO2/Au nanoparticles were irradiated with a low-energy laser (lambda = 808 nm) in a water suspension, which resulted in a photothermal effect and a temperature increase of 10 degrees C during the 10 min of irradiation. Furthermore, the results of experiments performed on a suspension of hybrid nanoparticles in a flow of water confirmed that they can be magnetically manipulated and retained at a targeted location under realistic dynamic conditions. This dual magnetic and optical effect makes the FePt/SiO2/Au hybrid nanoparticles excellent candidates for photothermal cancer treatments, with the added bonus of being able to magnetically extract the particles after their use.