Synthesis of magnetic glass-ceramic for hyperthermia treatment of cancer

Bioactive and ferromagnetic glass-ceramic is believed to be useful as thermoseeds for hyperthermiatreatment of cancer，自bonds to self well as to the bone to be fixed when it is implanted around tumor，那群人是受影响的地方up to 43゚C effective for cancer treatment by magnetichysteresis loss, when subjected to an alternating magnetic field. In the present studysynthesis of such bioactive and ferromagnetic glass-ceramic and application of it to the thermoseedswere investigated.A glass of the composition fe_2_340, CaO . sio_260, b_2_33，p_2_53 wt ratio precipitated magnetite 200 nm in size and 36wt % in amount in a matrix of CaO，sio_2 -based glassy phase and flu -wollastonite（CaO sio_2）when heated up to 1050゚C. The obtained glass-ceramics showed a ferromagnetism with saturationmagnetization of 32 emu/g and coercive force of 120 Oe as as well as bioactivity. About 5g of theglass-ceramic 0.1 to 1.0 mm in size filled into a marrow of rabbit tibia effectively heated outersurface of the tibia up to 43゚C，within 5 min after an alternating magnetic field of 100khz up to 300 Oe was applied. When a pin 3mm in diameter and 5cm in length of the glass-ceramic was inserted into amarrow of rabbit tibia towhich tumor had been transplanted, and subjected to the alternating magnetic field for 50 min，这是确认后3周，所有的cancer cells in the marrow，被完全killed by thehyperthermia treatment using the glass-ceramic。

Bioactive and ferromagnetic glass-ceramic is believed to be useful as thermoseeds for hyperthermia treatment of cancer, since it bonds to itself as well as to the bone to be fixed when it is implanted around tumor, and then the tumor is heated locally up to 43 ﾟC effective for cancer treatment by magnetic hysteresis loss, when subjected to an alternating magnetic field. In the present study, synthesis of such bioactive and ferromagnetic glass-ceramic and application of it to the thermoseeds were investigated.A glass of the composition Fe_2O_3 40, CaO・SiO_2 60, B_2O_3 3, P_2O_5 3 wt ratio precipitated magnetite 200 nm in size and 36 wt% in amount in a matrix of CaO, Sio_2-based glassy phase and fl-wollastonite(CaO・SiO_2), when heated up to 1050 ﾟC. The obtained glass-ceramics showed a ferromagnetism with saturation magnetization of 32 emu/g and coercive force of 120 Oe as well as bioactivity. About 5 g of the glass-ceramic 0.1 to 1.0 mm in size filled into a marrow of rabbit tibia effectively heated outer surface of the tibia up to 43 ﾟC, within 5 min after an alternating magnetic field of 100 kHz up to 300 Oe was applied. When a pin 3 mm in diameter and 5 cm in length of the glass-ceramic was inserted into amarrow of rabbit tibia to which tumor had been transplanted, and subjected to the alternating magnetic field for 50 min, it was confirmed after 3 weeks that all the cancer cells in the marrow were completely killed by the hyperthermia treatment using the glass-ceramic.