The study of nano-particles applied to biomedicine continues to give interesting results, as research is still in its infancy. Through their work, the chemists from the university of Cagliari are now investigating some of the possibilities opened by this field. One is to use magnetic particles to convey the drugs only to the diseased cells, the other is to drive up the tumor and then force them to oscillate under the control of a variable magnetic field, thereby heating the target cells, just like a microwave oven does with the water molecules contained in food.
This second mechanism exploits hyperthermia. It appears that cancer cells can be destroyed by beeing brought to a temperature of 42.5 degrees Celsius for about half an hour.
In order arrive at the place desired, the particles must be incorporated into liposomes, hollow microspheres formed by lipid bilayers (for which reason they are called "magneto-liposomes"), which are able to overcome the barrier of cells. They must have a diameter of about 20 nanometers. Larger could indeed block blood vessels, while smaller particles may be "eaten" by macrophage cells which are in charge with the elimination of foreign bodies.
Currently, the research team is working on the synthesis of particles and study of their structural and magnetic properties. Currently these are being built in oxide of iron or iron cobalt. The latter are more manoeuvrable, because their magnetic properties depend strongly on the direction along which the field is applied to (property known as magnetic anisotropy).
The researchers are also wondering how to remove the magnets once they have finished their work if they are iron oxide, the researchers explain, these can be eaten by macrophages, if they are cobalt ferrite they should be made to leave the body. The next step is a multidisciplinary study in collaboration with the departments of Pharmacy and Medicine to evaluate the toxicity and then move on to testing in vitro and in vivo in rats.