Nanomedicine and nanobiotechnology
(from the digest "Nanotechnology in the world" No. 2-2009)A biochip test system for the rapid detection of tick-borne infections (encephalitis, borreliosis and rickettsiosis) was created on the basis of nanotechnology by researchers of the Institute of Microbiology and Epidemiology of the East Siberian Center of the Russian Academy of Medical Sciences and employees of the Limnological Institute of the Siberian Branch of the Russian Academy of Sciences. The basic element of the chip is a nanocomposite film deposited on a hard surface (usually glass, metal, plastic or ceramics).
It is on it that the identification of the genetic material of pathogens is carried out. According to the head of the group, Yuri Dzhioev, the system is quite cheap and easy to create and operate ["AMI-TASS", 06.02.2009; RGRK "Voice of Russia", 17.02.2009].
Scientists have invented a tattoo for diabetics — nanosensors that monitor blood sugar levels when injected under the skin. The invention of American researchers will free diabetics from the procedure of blood sampling for analysis. Heather Clark and her colleagues from the Laboratory named after Charles Stark Draper (Draper Laboratory) was injected under the skin with nanoparticles with a diameter of 120 nm with a fluorescent dye, which is detected in infrared light when the glucose level increases. By replacing sensory molecules, it is possible to diagnose changes in the level of other substances, for example potassium. Clinical trials of nanosheets have not yet passed, but they have shown themselves well in animal experiments [TechnologyReview.com , 26.01.2009; NanoDigest.ru , 03.02.2009].
Alexander Ilyin's group from the Russian State Technological University (MATI-RSTU) has developed abrasion-resistant titanium endoprostheses. Due to the thermohydrogen treatment and nitrogen bombardment, a thin and durable layer of titanium nitride (ceramics) is formed on the surface. Today, MATI specialists use this technology for the manufacture of hip and knee joint endoprostheses, they are implemented by the Biomechanical Compatible Implants group of companies, created by Alexander Ilyin. 90% of the products are exported. In addition, MATI specialists have developed surgical fixators with shape memory, which are also in little demand in Russia ["Expert", 02/16/2009; website "Biomechanical compatible implants"].
Several Russian and foreign researchers report on the improvement of mechanical strength and survivability of prostheses made of nanostructured titanium. Vladimir Lunin and his colleagues from the Laboratory of Biologically Active Nanostructures of the N. F. Gamalei State Research Institute of Epidemiology and Microbiology use titanium with a grain size of about 100-300 nm, manufactured at the Ufa State Aviation Technical University. Implants made of such material are lighter, stronger and less damage to the bone. A relief is created on the surface of titanium with the help of special polishing — stem cells that form bone tissue are better attached to such a surface. Then a composite slurry is applied to titanium, which is similar in composition to bone tissue — collagen and hydroxylapatite. The composite also includes stem cell growth factors and bone protein. Where a composite is used, the bone grows twice as fast. The Ministry of Education and Science has allocated 140 million rubles for this project. ["Russian Reporter", 05.02.2009].
Professor Antonio Nanci from the University of Montreal and his colleagues use a different approach — they form the nanorelief of the surface of titanium implants by etching, rather than mechanical processing. Scientists have selected etching parameters that give the surface to which bone stem cells are most actively attached ["Nano Letters", 21.01.2009; NanoTechWire.com , 30.01.2009].
Engineers from the University of California in San Diego (University of California, San Diego) propose to cover titanium prostheses with titanium oxide nanotubes with a diameter of 70-100 nm, on which stem cells from the patient's bone marrow are applied. Sungho Jin and his colleagues have shown that at the same time, the rate of reproduction of stem cells increases by 10 times and they form bone tissue more actively. Thin nanotubes (about 30 nm in diameter) do not give the same effect. At the next stage, the developers of the new technology intend to obtain permission for clinical trials [PNAS, 28.01.2009; University of California at San Diego website, 30.01.2009; Cybersecurity.ru , 01.02.2009].
When creating nanocoats for implants, the laboratory of Karelian Pedagogical State University (KPSU) is not limited to titanium. Scientists also use oxide films made of aluminum and titanium alloys with a pore size of 10-300 nm. If you fill the pores with silver, you can create implants with good biocompatibility. Porous films can also be used as microbiological filters. The developments presented at the International Forum on Nanotechnology were recognized as promising from the point of view of commercialization [GTRK "Karelia", 26.01.2009].
The director of the Laboratory of Radiation Biology of the Joint Institute for Nuclear Research from Dubna near Moscow and his colleagues suggest using gold nanoclusters and microwave radiation for the treatment of melanoma. After being injected into the body, gold nanoclusters selectively bind to cancer cells. Under the influence of microwave radiation, they heat up and destroy target cells [Vesti-Moscow, 29.01.2009; official website of RosOEZ Dubna, 14.01.2009].
Scientists at the University of Washington have proposed a method that allows you to accurately determine the dose of gold nanoparticles and the power of infrared radiation during anti—cancer therapy - so that healthy cells do not suffer at the same time. Nanoparticles with antibodies on the surface selectively bind to cancer cells, and infrared irradiation heats them. This method has been proposed for a long time, but the question of dosage remained one of the most difficult [ACSNano, 25.07.2008; Nanometer, 25.01.2009] (In the picture: on the left – a cancer cell captures gold nanoparticles, on the right, with a smaller magnification, they look like small black dots.)
Portal "Eternal youth" www.vechnayamolodost.ru01.04.2009