Magnetic medicine hits the target
Swedish researchers have developed a way to use magnets to guide drugs to the right place in the body.
The technique uses magnetic nanoparticles which can be guided to metallic implants such as artificial joints and coronary stents. The researchers, based at Lund University and Skåne University Hospital, have shown in animal experiments that the principle works. They attached a blood clot-dissolving drug to the nanoparticles and then directed the particles to a coronary stent.
Guiding drug-loaded magnetic particles using a magnet outside the body is not a new idea. However, in the past it has only been possible to reach the body’s superficial tissue, and the particles have often obstructed the smallest blood vessels.
The new attempt succeeded partly because nanotechnology has made the particles tiny enough to pass through the smallest arteries, and partly because the target was a metallic stent - a tube-shaped metal net used to treat narrowing of the coronary arteries. When a magnetic field was applied to it, the stent itself became magnetic enough to attract the nanoparticles. For the method to work the patient therefore has to have an implant containing a magnetic metal.
According to the project’s leaders, Associate Professor Maria Kempe (pictured) and her brother and colleague Dr Henrik Kempe, if a drug can be guided to the right place in the body, the treatment is more effective and there should be fewer side-effects.
Maria Kempe added that the technique could be used with other drugs, and that there are a number of implant-related problems that could be targeted.
“They could also carry antibiotics to treat an infection developed after insertion of an implant. We have developed polymer materials that can be loaded with antibiotics – these could produce interesting results in this context,” she said. “It takes many years to develop a treatment method that can be used on patients. But the good initial results make us hopeful.”