The effect of pharmaceutical substances on the human organism, especially as one of the ingredients of new preparations, is a constant point of scientific interest. Anatoly Reshetilov, Dr. Sc. (Chem.), head of the Laboratory of Biosensors, RAS Institute of Biochemistry and Physiology of Microorganisms named after G. Skryabin, told about some discoveries in this field to Natalia Bulgakova, correspondent of the Poisk newspaper.

According to the scientist, "The human body is a most perfect sensor. It is very sensitive to different substances, but, as you understand, it will never be used as a test object." First of all, scientists focus on biosensors mainly "targeted" to analyze biological fluids,--appropriate devices are designed to register the presence and concentration of molecules of different chemical compounds in them. Electric signals can cope with this task, but the problem is that in case of molecules, there must be a great number of the substance under considera-

DNA molecule.

tion--about a million. National specialists formulated a task to be solved--to decrease the number of required molecules to one.

Earlier it took 15-30 min to determine glucose in blood; today biosensors make it possible to get the results in 10 sec. Transition to one molecule will accelerate the analysis procedure, which is very important for fundamental studies and a variety of applied tasks. For this purpose, it is necessary to reduce the size of electric signal transformers to a nanolevel. A group of scientists from the Pushchino branch of the Lomonosov Moscow State University Department of Physics and RAS Institute of Radio Engineering and Electronics named after V. Kotelnikov is working on this very problem: they are designing such transformers and a relevant measurement system for them and trying to find means to bring the molecule to electrodes and finally register an originating current. The first stage of the work--creation of transducers--has already been completed. At the moment, researchers are planning to make them more varied allowing to simultaneously measure the characteristics of substances under consideration by a number of biosensors. Nanobiotechnology will allow to reduce the time and cost of DNA sequencing.

N. Bulgakova, "We Don V Need a Million!", the Poisk newspaper, No. 40, 2010