Under the leadership of Petr Cígler of the Institute of Organic Chemistry and Biochemistry (IOCB Praga) and Martin Hrubý of the Institute of Macromolecular Chemistry (IMC), both of which are part of the Czech Academy of Sciences, a team of researchers has developed a Revolutionary Method for the Easy and economical production of irradiated nanodiamats and other suitable nanomaterials for use in diagnoses of highly sensitive diseases, including various types of cancer. Your article has been published recently in the scientific journal Natural communications.
Diagnosing diseases and understanding the processes that occur within cells at the molecular level require sensitive and selective diagnostic instruments. Nowadays, scientists can monitor the magnetic and electric fields in the cells with a resolution of several tens of nanometers and with remarkable sensitivity thanks to the crystal defects in the particles of certain inorganic materials. An almost ideal material for these purposes is diamond. Compared to the diamonds used in jewelry, those used for diagnostic applications and nanomedicine – nanodiamonds – are approximately one million times smaller and are produced synthetically from high pressure graphite and temperatures.
A pure nanodevideo, however, does not reveal much about its environment. In the first place, its crystalline network must be damaged under controlled conditions to create special defects, so-called nitrogen vacuum centers, which allow the obtaining of optical images. The damage is most commonly created by the irradiation of nanodiamonds with fast ions in particle accelerators. These accelerated ions are capable of hitting carbon atoms outside the crystalline screen of a nanodiamond, leaving the holes known as squares, which at high temperatures bind to the nitrogen atoms present in the crystal as pollutants. Newly formed vacuum nitrogen centers are a source of fluorescence, which can then be observed. It is precisely this fluorescence which provides the nanodiamonds with immense potential for applications in medicine and technology.
However, a fundamental restriction on the use of these materials at a wider scale is the high cost and poor efficiency of irradiating ions in an accelerator, which prevents the generation of this material exceptionally valuable in large quantities.
The team of scientists from several research centers headed by Petr Cígler and Martin Hrubý recently published an article in the magazine Natural communications describing an entirely new method of nanocrystalline irradiation. Instead of a costly and slow irradiation in an accelerator, scientists exploded irradiation in a nuclear reactor, which is much faster and much less expensive.
But it was not that simple. Scientists have had to use a trick: in the reactor, the neutron irradiation separates the boron atoms in very light and fast ions of helium and lithium. Nanocrystals must first be dispersed in molten boron oxide and then subjected to neutron irradiation in a nuclear reactor. The capture of neutrons by boron nuclei produces a dense shower of helium and lithium ions, which have the same effect within the nanocrystals that the ions produced in an accelerator: the controlled creation of crystal defects. The high density of this particle shower and the use of a reactor to radiate a much larger amount of material means that it is easier and much more accessible to produce dozens of grams of rare nanomaterials at the same time, which is approximately a thousand times more than scientists. until now they have been able to obtain through comparable irradiation in accelerators.
The method has proved to be successful not only in the creation of defects in the nanodiamonds network, but also in another type of nanomaterial – silicon carbide. For this reason, scientists assume that the method could find a universal application in the large-scale production of nanoparticles with defined defects.
The new method uses the principle applied in boron neutron capture (BNCT) therapy, where a boron compound is administered. Once the compound has collected in the tumor, the patient receives radiation with neutrons, which divide the boron nuclei into helium and lithium ion. These then destroy tumor cells that boron collected. This principle derived from the experimental cancer treatment thus opened the door to the efficient production of nanomaterials with an exceptional potential of applications, among others, of the diagnosis of cancer.