Magnetic nanoparticles: Suitable for cancer therapy?

May 28, 2008

A measuring procedure developed in the Physikalisch-Technische Bundesanstalt (PTB) can help to investigate in some detail the behaviour of magnetic nanoparticles which are used for cancer therapy.

Magnetic nanoparticles (with a size of some few to several hundred nanometres) are a new, promising means of fighting cancer. The particles serve as a carrier for drugs: "loaded" with the drugs, the nanoparticles are released into the blood stream, where they move until they come under the influence of a targeting magnetic field which holds them on to the tumour – until the drug has released its active agent.

Besides this pharmaceutical effect, also a physical action can be applied: an electromagnetic a.c. field heats up the accumulated particles so much that they destroy the tumour. Both therapeutic concepts have the advantage of largely avoiding undesired side effects on the healthy tissue.

These procedures have already been successfully been applied in the animal model and have, in part, already been tested on patients. Here it is important to know before application whether the particles tend to aggregate and thus might occlude blood vessels.

Information about this can be gained by magnetorelaxometry developed at the PTB. In this procedure, the particles are shortly magnetised by a strong magnetic field in order to measure their relaxation after the switch-off of the field by means of superconducting quantum interferometers, so-called "SQUIDs".

Conclusions on their aggregation behaviour in these media can be drawn from measurements of suspensions of nanoparticles in the serum or in whole blood. As an example, it could be shown in this way that certain nanoparticles in the blood serum form clusters with a diameter of up to 200 nm – a clear indication of aggregation, so that these nanoparticles do not appear to be suitable for therapy.

At present, the high technical effort connected with the use of helium-cooled magnetic field sensors is still standing in the way of using this method routinely in practice. In a joint project with Braunschweig Technical University supported by the Ministry of Education and Research (BMBF), the procedure is currently being transferred to a simpler technology based on fluxgate magnetometers.

Source: Physikalisch-Technische Bundesanstalt

Explore further: New tool for studying magnetic, self-propelled bacteria that resemble compass needles

Related Stories

Biomimetic dental prosthesis

September 27, 2015

There are few tougher, more durable structures in nature than teeth or seashells. The secret of these materials lies in their unique fine structure: they are composed of different layers in which numerous micro-platelets ...

Sandcastles inspire new nanoparticle binding technique

August 5, 2015

If you want to form very flexible chains of nanoparticles in liquid in order to build tiny robots with flexible joints or make magnetically self-healing gels, you need to revert to childhood and think about sandcastles.

Recommended for you

Dielectric film has refractive index close to air

October 12, 2015

Researchers from North Carolina State University have developed a dielectric film that has optical and electrical properties similar to air, but is strong enough to be incorporated into electronic and photonic devices - making ...

Have your drug nano-delivered via microbubble

October 12, 2015

"Colloidal delivery system" and "nanoparticle" are probably not terms you find yourself using in day-to-day interactions, but for UC's Yoonjee Park, assistant professor in the College of Engineering and Applied Science biomedical ...

Gold nanomembranes resist bending in new experiment

October 9, 2015

The first direct measurement of resistance to bending in a nanoscale membrane has been made by scientists from the University of Chicago, Peking University, the Weizmann Institute of Science and the Department of Energy's ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet May 29, 2008
If you can COOL the cell you can DE-CELERATE MITOSIS!

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.