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 Noninvasive eye scan could detect key signs of Alzheimer's years before patients show symptoms
18.08.2017 | Cedars-Sinai Medical Center

nachricht Water-filtered infrared-A (wIRA) overcomes swallowing disorders and hypersalivation – a case report
10.08.2017 | Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften e.V.

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>