Copper based nanoparticles (Cu-based NPs) of different composition and sizes have been hydrothermally synthesized by varying the reaction temperature and in the presence of biocompatible surfactants; polyoxyethylene (20) sorbitan laurate, polyethylene glycol 1000 and polyethylene glycol 8000. Effective control of the above synthetic parameters gave rise to Cu-based NPs of 11–55 nm. CuO, Cu₂O nanoparticles and Cu/Cu₂O composite nanoparticles of nearly similar size and shape were selected among the isolated samples and tested in the field on tomato (Lycopersicon esculentum) plants against Phytophthora infestans. Their activity has been evaluated by assessing the fungal infection on the leaves in comparison to the performance of the registered commercially used copper based products Kocide 2000, Kocide Opti, Cuprofix disperss and Ridomil Gold Plus. The results showed that the prepared Cu-based NPs can be applied in a lower formulated product and active ingredient rate and are more effective than the trade agrochemicals. Moreover, assessments regarding phytotoxicity indicated that they can be used without any deleterious effect on plants.

MnFe ₂ O ₄ nanoparticles of low inversion degree present optimized magnetization with high ( T ₂ ) relaxation (345.5 s ⁻¹ mM ⁻¹ ) and heating efficiency (286 W g ⁻¹ ).

Nickel ferrite nanoparticles were synthesized via a facile solvothermal approach. Oleylamine (OAm) was used in all synthetic procedures as a stabilizing agent and solvent. By varying the polarity of the solvents, hydrophobic NiFe₂O₄ nanoparticles coated with OAm of relatively similar sizes (9–11.7 nm) and in a range of magnetization values (32.0–53.5 emu g⁻¹) were obtained. The as-prepared hydrophobic nanoparticles were characterized by XRD, TEM, SEM, TGA and VSM and converted to hydrophilic by two different approaches. The addition of a positively charged ligand (cetyltrimethyl ammonium bromide, CTAB) and the ligand exchange procedure (2,3-dimercaptosuccinic acid, DMSA) have been successfully applied. The aqueous suspensions of NiFe₂O₄@CTAB and NiFe₂O₄@DMSA showed good colloidal stability after a long period of time. The different surface modification affected both the NMR relaxometric measurements and the hyperthermia effects. In both techniques CTAB modification demonstrated higher r₂ relaxivity (278.9 s⁻¹ mM⁻¹ in an NMR spectrometer at 11.7 T) and SAR values (423.4 W g⁻¹ at an applied AC field with a particle concentration of 0.5 mg mL⁻¹). The results indicate that a coating with a larger molecule as CTAB under the same size, shape and magnetization of NiFe₂O₄ NPs gave rise to NMR relaxometric properties and heating efficacy.