Sr-doped CuFe₂O₄ nanoparticles: Exploring structural, magnetic, and blood compatibility characteristics

The aim of this study is to investigate the structural, magnetic, and blood compatibility properties of Sr²⁺ substituted for Cu²⁺ in Cu_1−xSr_xFe₂O₄ (x = 0.0 to 1 with a 0.25 increment) nanoparticles synthesized via the sol-gel auto-combustion technique. Regardless of the substitution rate, the sol-gel auto-combustion method consistently yields powders with sizes ranging from 20 to 40 nm. The specific surface area of the produced powders is determined as 12 m²/g. X-ray diffraction analysis reveals that CuFe₂O₄ exhibits a singular phase; however, as the Sr²⁺ ion substitution increases, the emergence of various secondary phases becomes apparent, with their proportions increasing with the substitution rate. The magnetic characteristics of the synthesized powders exhibit variations in magnetization, correlating with the distribution of cations in the sublattice points. Coercivities are influenced by both anisotropy and secondary phases. Saturation magnetization decreases from 31.3 (CuFe₂O₄) to 7.6 (SrFe₂O₄) emu/g with Sr replacement. The lowest observed coercivity is 429.5 Oe in powders prepared with CuFe₂O₄ composition, while the highest is measured at 583.8 Oe in nanopowders prepared with Cu_0.5Sr_0.5Fe₂O₄ composition. Moreover, blood compatibility experiments indicate significantly low hemolysis ratios for Cu_1−xSr_xFe₂O₄ nanoparticles. Additionally, all examined samples exhibit an increase in Soret band intensity compared to the negative control test, suggesting potential biocompatibility.