Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

More light on cancer

20.05.2016

Scientists created nanoparticles to highlight cancer cells

The group of Russian and French researchers, with the participation of scientists from the Lomonosov Moscow State University, has succeeded to synthesize nanoparticles of ultrapure silicon, which exhibited the property of efficient photoluminescence, i.e., secondary light emission after photoexcitation. These particles were able to easily penetrate into cancer cells and it allowed to use them as luminescent markers in the early diagnosis of cancer and in treatments of this disease. The article was published in the journal Scientific Reports.


These are confocal fluorescence microscopy images of CF2Th cancer cells incubated with LA-Si NPs.

Credit: Victor Timoshenko/Scientific Reports

Investigations to find methods for synthesizing such nanoparticles are actively conducted in many laboratories around the world, however, according to one of the study co-authors, professor of the Physics Department of the Lomonosov Moscow State University, Victor Timoshenko, the particles' quality was poor, mainly because they were synthesized by chemical reactions in acid solutions.

'The obtained particles were not sufficiently pure,' he says. 'By-products of the chemical reactions made them toxic. Furthermore, these nanoparticles had a form, which was far from a sphere, and it does not contribute to the appearance of the photoluminescence. These two drawbacks severely restricted their applications'.

To get rid of these shortcomings, the researchers decided to use a different method, with no positive results previously -- the so-called laser ablation, i.e. the ejection of atoms from the target with a laser beam, so that the torn atoms would form a nanocrystal then.

The problem here was that the atoms torn in this case often did not combine to particles, but to some arbitrary layers, and even if the nanoparticles were obtained, they did not shine. It happened as either the nanoparticles were too large, or they cool down too quickly and did not have time to form high-quality nanocrystals. In other words, it was necessary to warm them, to encourage crystallization for a very short time.

'For that purpose, we decided to use high-intensity, short laser pulses,' Professor Timoshenko says. 'They not only ejected the silicon atoms from the target, but additionally ionized them. The emitted electrons led to the ionization of helium atoms, in which atmosphere it all was happening.

In a very short time of nanoseconds something of a microwave kind appeared, laser plasma formed the conditions that allowed the atoms to sinter into spherical nano-crystals. These beads falling onto the surface aggregated as a fluffy layer, which subsequently could be readily dispersed in water'.

These nanoparticles had spherical shape and were just the right size -- 2-4 nanometers in diameter -- which, as physicists have well known, provided efficient photoluminescence where each falling photon is balanced with one ejected. In contrast to nanoparticles obtained by chemical etching, they were deprived of toxic additives. And most importantly, as demonstrated by biological experiments, they could easily penetrate into the cells.

Moreover, into the cancer cells such nanospheres penetrate much more readily than into the healthy ones. This is due to the fact that the cancer cells are always ready to divide, always absorbs everything around to give rise to daughter cells. According to Victor Timoshenko, depending on the type of cells, cancer cells typically absorb nanoparticles 20-30% percent more efficiently than the healthy ones, and this can already lay a basis for the diagnostic of cancer at its' early stage.

'Our main achievement was that we produced such nanoparticles and established that they easily penetrate into cancer cells,' Victor Timoshenko said. 'The problem of the diagnostic is a separate task, which is solved simultaneously by biologists, with our participation. You can, for example, replace the analysis of biopsy, a fairly long and not too reliable "yes-no" test, in which the cancer cells in the body are detected by the fact whether a nanoparticle penetrated a tissue sample, or it did not.

There are also non-invasive diagnostic methods. The photoluminescent light emitted from the nanoparticles in this case is difficult to use, but they can be activated by other means, for example, ultrasound or radio frequency electromagnetic waves'.

The main advantage of the obtained nanoparticles is that they are completely non-toxic and easily excreted. But their advantage is not reduced to that. They also can attach specific substance or group of biomolecules (e.g., antibodies) to their surface, allowing us to target them to penetration into cancer cells and thereby increase the efficiency of diagnosis. According to Victor Timoshenko, in the future those obtained nanoparticles will also have the drug attached, that will not only detect cancer, but also help to conduct a local chemotherapy or radiotherapy on the cellular level.

Media Contact

Vladimir Koryagin
science-release@rector.msu.ru

http://www.msu.ru 

Vladimir Koryagin | EurekAlert!

More articles from Health and Medicine:

nachricht A promising target for kidney fibrosis
21.04.2017 | Brigham and Women's Hospital

nachricht Stem cell transplants: activating signal paths may protect from graft-versus-host disease
20.04.2017 | Technische Universität München

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>