Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


More light on cancer


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 

Vladimir Koryagin | EurekAlert!

More articles from Health and Medicine:

nachricht Advanced analysis of brain structure shape may track progression to Alzheimer's disease
26.10.2016 | Massachusetts General Hospital

nachricht Indian roadside refuse fires produce toxic rainbow
26.10.2016 | Duke University

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: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>