The purpose of this study was to investigate the cell necrosis by the hysteric heating of Co1-xNixFe2O4 and Ba1-xSrxFe12O19 ferrites under external magnetic field with respect to applications in hyperthermic cancer treatments. Co1-xNixFe2O4 and Ba1-xSrxFe12O19 ferrites were synthesized by a sol-gel process. Variation of the temperature as a result of hysteresis heating was measured as a function of the exposure time to the external alternating magnetic field at frequencies of 0.1 - ~ 15 MHz. A human squamous cell carcinoma KB cell line was selected to determine the effect of the synthesized ferrites on the destruction of carcinoma cells in vitro using a methylthiazol tetrazolium bromide (MTT) method. When a CoFe2O 4 disc was placed in 0.2 ml of distilled water, the greatest temperature change (ΔT = 29.3°C) was observed. More than half of the malignant carcinoma cells were dead after being exposed to the 7-MHz ac magnetic field for 1 h by CoFe2O4 ferrites, while normal cells survived more than 60% of the time.
Bibliographical noteFunding Information:
Manuscript received October 16, 2003. This work was supported by Grant R01-2001-000-00157 from the Basic Research Program of the Korea Science and Engineering Foundation.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering