Enhanced specific loss power of hematite-chitosan nanohybrid synthesized by hydrothermal method

We used a hydrothermal technique to develop nano-scale alpha-Fe2O3 particles and functionalized them with chitosan. An X-ray diffraction study revealed alpha-Fe2O3 nanoparticles were of single-phase, lattice constants were a = 5.07 angstrom and c = 13.68 angstrom, and the grain size was 27 nm. The presence of lattice fringes in the HRTEM image confirmed the crystalline nature of the alpha-Fe2O3. The Mossbauer spectra reveal a mixed relaxation state, which supports the PPMS studies. Zero-field cooled studies revealed the existence of a Morin transition and blocking temperature. The z-average value of the coated particles by DLS was between 218 and 235 nm, PDI ranged from 0.048 to 0.119, and zeta potential was +46.8 mV. We incubated the Vero and HeLa cell lines for 24 h to study the viability of the nanohybrids at different concentrations. Hyperthermia studies revealed the maximum temperature and specific loss power attained by the hematite-chitosan nanohybrid solution of a concentration between 0.25-4 mg ml-1. The Tmax at the lowest and highest concentrations of 0.25 and 4 mg ml-1 were 42.9 and 48.3 degrees C, while the SLP were 501.6 and 35.5 W g-1, which are remarkably high when the maximum magnetization of alpha-Fe2O3 nanoparticles was as small as 1.98 emu g-1 at 300 K.

Automated summary

In this study, nano-scale alpha-Fe2O3 particles were prepared using a hydrothermal technique and functionalized with chitosan. The results showed that the alpha-Fe2O3 nanoparticles had a single-phase structure with expected lattice constants and grain size. Additionally, the chitosan-coated particles exhibited a high zeta potential. Cell culture and hyperthermia experiments demonstrated that the nanohybrids had high maximum temperature and specific loss power within a certain concentration range.