  Demonstrating highly efficient alternating current (AC) magnetic field
heating of nanoparticles in physiological environments under clinically safe
field parameters has remained a great challenge, hindering clinical
applications of magnetic hyperthermia. In this work, we report exceptionally
high loss power of magnetic bone cement under clinical safety limit of AC field
parameters, incorporating DC field-aligned soft magnetic Zn0.3Fe2.7O4
nanoparticles with low concentration. Under an AC field of 4 kA/m at 430 kHz,
the aligned bone cement with 0.2 wt% nanoparticles achieved a temperature
increase of 30 C in 180 s. This amounts to a specific loss power value of 327
W/gmetal and an intrinsic loss power of 47 nHm^2/kg, which is enhanced by
50-fold compared to randomly oriented samples. The high-performance magnetic
bone cement allows for the demonstration of effective hyperthermia suppression
of tumor growth in the bone marrow cavity of New Zealand White Rabbits
subjecting to rapid cooling due to blood circulation, and significant
enhancement of survival rate.
