2.3.3. Multifunctional hybrid systems 2.3.4. High magnetic moment core@shell nanoparticles 2.4. Instrumentation for magnetic-induced hyperthermia 3. Photo-induced hyperthermia 3.1. Mechanisms of Photo-induced hyperthermia 3.1.1. Surface plasmon resonance absorption 3.1.2. Interactions between light and carbon reticle vibrational state 3.1.3. Generation of heat in nanoparticles: role of non-radiative recombination 3.2. Parameters affecting the photo-induced hyperthermia 3.3. Potential photo-induced hyperthermia nanomaterial 3.3.1. Carbon Nanostructures 3.3.2. Au nanomaterials 3.3.3. Iron oxide nanoparticles (IONPs) and Ferrites 3.3.4. Quantum Dots (QDs) 3.3.5. Rare-earth containing NPs 3.4. Instrumentation for photo-induced hyperthermia 4. Comparison between magnetic and photo-induced hyperthermia and their combinatorial effect 5. Prerequisites for hyperthermia treatment in the clinic 5.1. Parameter affecting toxicity: size, shape, composition, coating 5.2. Biodistribution, pharmacokinetics and clearance rate 5.3. Concentration required for treatment 5.4. Drug release by external thermal therapy 5.5. In vivo and clinical application of hyperthermia treatments 5.5.1. Tumor microenviroment and hyperthermia effects 5.5.2. Delivery routes of nanoparticles in tumors 5.5.3.Examples of in vivo and clinical application of hyperthermia treatment 6. Conclusion and future perspectives Conflict of interest:

To investigate the role of magnetic anisotropy on magnetic hyperthermia heating efficiency at low field conditions, Mn, MnZn, and MnCo-ferrite nanoparticles were synthesized using the hydrothermal method. The coercive field temperature dependence method was used to determine the blocking temperature distribution of the particles by considering the temperature dependence of anisotropy and magnetization and the random anisotropy axis configuration. The data allowed one to estimate the room-temperature quasi-static superparamagnetic diameter, which was found to be lower than the theoretical value. Magnetic hyperthermia experiments of the magnetic nanocolloids at 522 kHz indicated that soft nanomagnets heat more efficiently at clinically relevant conditions. The heating performance was found to decrease at the higher fraction of blocked nanoparticles. For instance, samples with similar size distribution and mean diameter of 10 nm, at a field amplitude of only 120 Oe (9.6 kA m–1), showed a decrease of specific loss power of 56% for the Mn-ferrite and 93% for the MnCo-ferrite in comparison with the MnZn-ferrite nanoparticle. The fractions of blocked particles of the MnZn, Mn, and MnCo-ferrite were 5, 10, and 25%, respectively, at room temperature.

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Multifunctional magnetic nanoparticles (NPs) that can generate and monitor heat (in real-time) during thermal therapy are a major challenge in nanomedicine. Here, we report a trimodal system combining magnetic NP hyperthermia (MNH), photothermal therapy (PTT), and luminescent nanothermometry (LNT) properties with an all-in-one nanoplatform. Zinc–manganese ferrite NPs were optimized focusing on low field MNH, where Zn0.3Mn0.7Fe2O4 proved as a competitive nanoheater at clinically relevant conditions. Further, SiO2-coated Zn0.3Mn0.7Fe2O4/cit. with embedded Nd3+ (Zn0.3Mn0.7Fe2O4@SiO2:Nd) NPs were prepared for the potency of multifunctionality as LNT and enhanced PTT. Photothermal conversion efficiency (PCE), at low laser power conditions (1.5 W/cm2), varied from 17% for silica-coated magnetic NPs to 24% after embedding 1 mmol of Nd3+ in the SiO2 matrix. Increasing laser power to 11.8 W/cm2 decreased the PCE of Zn0.3Mn0.7Fe2O4@SiO2:Nd to 9%, but this deleterious effect was reduced significantly by the shell engineering strategy, that is, increasing the shell thickness Zn0.3Mn0.7Fe2O4@ SiO2@SiO2:Nd that maintained a PCE value of 18%. Additionally, as a potential nanothermometer, with excitation around 800 nm and emission at the second biological window, the thermal sensitivity of the system was found to be ∼1.1 % K–1 at 300 K (27 °C), ∼ 1.4% K–1 at 316 K (43 °C), and ∼1.5% K–1 at 319 K (46 °C). Additionally, simultaneous heating effects due to magnetic fields and photoexcitation (808 nm) on Zn0.3Mn0.7Fe2O4@SiO2@SiO2:Nd show synergy effects between MNH and PTT. Because of the high hemolytic activity toward the red blood cells due to the SiO2 layer, we also demonstrate that surface coating the nanocarrier with bovine serum albumin drastically reduced the hemolytic activity providing a capability for future in vivo applications with this multifunctional nanocarrier.