Magnet Nanoparticles Guide Drugs to Targets in the Body

Researchers at Lund University in Sweden have developed magnetic nanoparticles that can be directed to metallic implants such as coronary stents and artificial knee and hip joints. Using this strategy, drugs could be delivered to targeted areas in the body to dissolve blood clots in the arteries or reduce inflammation after metallic joints have been surgically implanted. Potential benefits include improved outcomes for patients with fewer side-effects than conventional drug-delivery methods.

Associate Professor Maria Kempe, her brother and colleague Dr Henrik Kempe and members of staff at Skåne University Hospital have shown that the principle works with metal stents in animal experiments. They succeeded in attaching a clot-dissolving drug to the nanoparticles and, using magnets, directed the particles to a blood clot in a stent to dissolve it, potentially preventing a heart attack in the process.

Maria Kempe

In the experiments, the nanoparticles were coated with a drug used to treat blood clots. The particles also could carry drugs that stop cell growth that result in arterial narrowing. “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,” says Maria Kempe.

Guiding drug-loaded magnetic particles using a magnet outside the body is not a new idea. However, previous attempts have failed for various reasons: it has only been possible to reach the body’s superficial tissue and the particles have often obstructed the smallest blood vessels.

The researchers’ attempt has succeeded partly because nanotechnology has made the particles tiny enough to pass through the small arteries and partly because the target has been a metallic stent. When the stent is placed in a magnetic field, the magnetic force becomes sufficiently strong to attract the magnetic nanoparticles. ”It takes many years to develop a treatment method that can be used on patients. But the good initial results make us hopeful,” says Maria Kempe.

More information on the technology can be found from Lund Universitet. A video (without sound) showing how the technology works can be viewed on the Lund Universite page as well.

Tags: Drug delivery, Lund University, Maria Kempe, Skåne University Hospital