Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Goodbye, implants rejection!

05.08.2016

Physicists of Moscow State University have created a magnetic field which helps avoid implants rejection

A group of Russian physicists, with the contribution from their Swiss colleagues, developed a way to use the therapeutic effect of heating or cooling the tissues due to the magnetocaloric effect. The article with the results of the work was published in the latest issue of the International Journal of Refrigeration.


These are coated polypropylene samples of implants (abdominal nets)

Credit: Vladimir Zverev

A team of the Lomonosov Moscow State University scientists proposed a new way to use the magnetocaloric effect for the targeted delivery of drugs to the implants. Vladimir Zverev, one of the authors (Lomonosov Moscow State University, Faculty of Physics) claims that this is a unique method that uses a negative magnetocaloric effect.

The gist of the magnetocaloric effect (MCE) is reduced to the fact that when exposed to an external magnetic field, the magnetic material changes its temperature, sometimes rising and sometimes, on the contrary, falling (depending on the material). This significant physical phenomenon was discovered in the nineteenth century, although the effect has been described only in 1917. Over the past century, the MCE has been minutely studied, but the interest of researchers increased dramatically in recent decades. This is due to, first, a significant contribution to the physics of magnetic materials, and, second, a fairly extensive area of its possible applications. It can be very successfully used in low-temperature physics, for the production of heat engines, refrigeration and so on.  

 However, the majority of these applications is not ready for commercial use yet, mainly due to the unavailability of the technology. Speaking, for example, about domestic magnetic refrigerators, although they are being developed today by many scientific and industrial laboratories around the world, according to Vladimir Zverev, a member of the Physics Department of MSU, such refrigerators, if they were made today, would be very expensive.

'For such a refrigerator magnetic field of around one Tesla is required, which at today's possibilities makes the prices very high and therefore commercially unacceptable - the very device to generate such a field will cost at least fifteen hundred dollars. It remains to wait for them to fall in price', Vladimir Zverev says.  

However, this did not prevent the authors from suggesting a new application of the magnetocaloric effect, almost ready for massive use - this time in medicine.  

One of the developed methods is called "magnetic fluid hypothermia" and consists in heating cancer tumors with special magnetic nanoparticles, delivered directly to the tumor site. To do this, the researchers developed and created a unique tool to create an alternating high-frequency magnetic field with no analogues in the world, as Vladimir Zverev says. Today, with the help of this facility in the Blokhin Scientific Cancer Centre, the primary research of various cancerous cell cultures was conducted.

The studies on mice were also carried out, which proved biocompatibility and non-toxicity of the microparticles. The experiments on the microparticles' pharmacokinetics are conducted as well, which demonstrate its ability of retention in the tumor, spreading in the body with the blood flow etc.  

 If the possibility of using such magnetocaloric effect in the scientific literature is at least mentioned - in fact that the heating of the tumor may lead to its degradation has long been known, - the second method, proposed by the scientists, is quite unique.

 It is known that one of the problems when implanted of foreign parts in human- artificial joints, abdominal nets, stents esophagus, urinary and biliary ducts, etc. - is the likelihood of rejection. The authors offer to apply a special coating to implants (yet at the stage of the preparation for installing), consisting of several layers. The first layer is a magnetic material, which is cooled in an external magnetic field (a material with a negative magnetocaloric effect).

This layer may be a thin film or a suspension of magnetic microparticles. The second layer is the polymer matrix, in which, as a sponge, absorbs the drug. The polymer matrix is in direct thermal contact with the magnetocaloric material. This entire structure is placed in the body during the operation.

The fact that the polymer used in the technology at the normal body temperature, i.e. at a temperature above 37 degrees, behaves like a jelly, which holds the drug inside. When the magnetic field lowers the temperature, the polymer transits in a liquid state and releases drug at the site of theimplantation. For example, when, after insertion of the implant an inflammation occurs, the non-invasive application of an external magnetic field (for example, in MRI) allows to release the desired dose of drug over the desired time and place.

This method of the 'targeted' drug delivery is good, in particular, by the fact that it only affects the source of inflammation and remains the rest of the body uninfluenced, that is, by definition, completely harmless. There is a problem though - it is unclear what to do if the coated drug is over.

Zverev says that this problem is solvable: 'First, in some cases just a single drug input is need, for example, to paste the abdominal mesh. A release dosage portions of the drug can be controlled by regulating the magnitude of the external magnetic field. It is also possible to replenish a the coat, using the fact that a drug may be chemically linked to the magnetic particles which can be 'dragded' to the desired location in the body by an external magnetic field. This method we haven't developed however, and it is only ideas yet'.

Media Contact

Vladimir Koryagin
science-release@rector.msu.ru

http://www.msu.ru 

Vladimir Koryagin | EurekAlert!

More articles from Medical Engineering:

nachricht Novel PET tracer identifies most bacterial infections
06.10.2017 | Society of Nuclear Medicine and Molecular Imaging

nachricht Teleoperating robots with virtual reality
05.10.2017 | Massachusetts Institute of Technology, CSAIL

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>