Turning the heat on cancer
doi:10.1038/nindia.2008.143 Published online 13 March 2008
Researchers in Mumbai have created special magnetic nanoparticles in fluid that could help generate heat in the body to kill cancer cells. The nanoparticles also show promise in enhancing the contrast factor in magnetic resonance imaging (MRI) — an indispensable diagnostic tool to detect fatal diseases like cancer.
Ferrofluid is a nano-sized iron-based magnetic particle in an organic solvent. In recent times, such nanoparticles have gained importance in biomedicine. Other researchers have tried to coat these particles with several surfactant and polymers (citrate, polyaspertic acid, and dextran) to increase their biocompatibility. But, there has been a pressing need for water-based more biocompatible ferrofluid.
Using salts of manganese chloride, iron chloride, cobalt chloride and ammonium chloride, the researchers produced the new ferrite nanoparticles. They added a fatty acid (lauric acid) and water to the wet-washed ferrite nanoparticles. The mixture was kept on a hot plate and stirred to form ferrofluid.
The average particle size of the particles is around 80 nm. The researchers worked with two types of nanoparticles, one having manganese and the other cobalt. The cobalt nanoparticles proved to be more toxic in compatibility studies on cultured cervical cancer cells.
During fever, the human body defends itself by increasing temperature to thwart the proliferation of deadly bugs. The magnetic nanoparticles could work wonders in hyperthermia, where body temperatures are raised as a therapy.
"These ferrofluids are stable for more than 12 months and don't precipitate," says lead researcher Dhirendra Bahadur from the Department of Metallurgical Engineering and Materials Science at the Indian Institute of Technology, Mumbai.
- Giri, J. et al. Synthesis and characterizations of water-based ferrofluids of substituted ferrites [Fe1-xBxFe2O4, B=Mn, Co (x=0-1)] for biomedical applications. J. Magn. Magn. Mater. 320, 724-730 (2008) doi: 10.1016/j.jmmm.2007.08.010