[AFM fishing of proteins under impulse electric field]. / ASM-fishing belka v impul'snom élektricheskom pole.

A combination of (atomic force microscopy)-based fishing (AFM-fishing) and mass spectrometry allows to capture protein molecules from solutions, concentrate and visualize them on an atomically flat surface of the AFM chip and identify by subsequent mass spectrometric analysis. In order to increase the AFM-fishing efficiency we have applied pulsed voltage with the rise time of the front of about 1 ns to the AFM chip. The AFM-chip was made using a conductive material, highly oriented pyrolytic graphite (HOPG). The increased efficiency of AFM-fishing has been demonstrated using detection of cytochrome b5 protein. Selection of the stimulating pulse with a rise time of 1 ns, corresponding to the GHz frequency range, by the effect of intrinsic emission from water observed in this frequency range during water injection into the cell.

Detection of microwave radiation of cytochrome CYP102 A1 solution during the enzyme reaction.

Microwave radiation at 3.4-4.2 GHz frequency of the cytochrome P450 CYP102 A1 (BM3) solution was registered during the lauric acid hydroxylation reaction. The microwave radiation generation was shown to occur following the addition of electron donor NADPH to a system containing an enzyme and a substrate. The radiation occurs for the enzyme solutions with enzyme concentrations of 10-8 and 10-9 Ðœ. The microwave radiation effect elicited by the aqueous enzyme solution was observed for the first time. The results obtained can be used to elaborate a new approach to enzyme systems research, including studying of the mechanism of interaction of a functioning enzyme system with microenvironment.

Monitoring of microwave emission of HRP system during the enzyme functioning.

Monitoring of microwave emission from aqueous solution of horseradish peroxidase (HRP) in the process of the enzyme functioning was carried out. For the monitoring, a system containing HRP, luminol and Н2О2 was employed. Microwave emission measurements were carried out in the 3.4-4.2 GHz frequency range using the active and passive modes (active-mode and passive-mode measurements). In the active mode, excitation of the solution in the pulsed electromagnetic field was accomplished. In the passive mode, no excitation was induced. It appears that the passive-mode measurements taken in the course of the peroxidase reaction in the enzyme system have shown a 0.5 °Ð¡ increase of the microwave signal. Upon the active-mode measurements, taken in the same reaction conditions, the forced excitation of the solution has also led to the increase (by 2 °Ð¡) of the level of the microwave signal - i.e. to its 4-fold enhancement compared to the signal obtained in passive-mode measurements.

[Registration of the protein in the serum with a field-effect nanotransistor biosensor].

A method for detection of cancer-associated protein D-NFATc1 in serum using nanowire (NW) biosensor based on field-effect nanotransistor is developed. Field-effect nanotransistor was fabricated on the basis of «silicon-on-insulator¼ structures. For the biospecific detection of target protein, the NW surface was modified with aptamers against the target protein. Using the 3 um-NW enabled to obtain stable source-drain characteristics and to register D-NFATc1 in serum at concentration of 2.5 x 1014 M in the mode of drain-source current vs. gate voltage characteristics measurements. Data collection in the mode of drain-source current vs. gate voltage characteristics measurements was carried out with the use of high-speed data collection system running TURBO NBS software.

SHF radiation from albumin solution upon external excitation.

The purpose of the research consisted in the measurement of nonequilibrium radiation in superhigh frequency (SHF) range from aqueous solution of albumin upon its mechanical stimulation. Methods: the monitoring of change in the ratio between brightness temperatures TSHF and TIR values after the mechanical stimulation of aqueous solution of albumin in the measuring cell at 35-39°Ð¡. The measurements of brightness temperatures were carried out with use of radiothermometer. SHF frequency range corresponded to 3.4-4.2 GHz, SHF frequency range corresponded to 8-13 mm. Results: It was found that mechanical stimulation of aqueous solution of albumin at the temperature ~39°Ð¡, the change in the ratio between TSHF and TIR occurs. This corresponds to emergence of nonequilibrium SHF radiation from the solution near the phase transition with ~39°Ð¡ temperature. Conclusion: The effect of emergence of nonequilibrium SHF radiation from protein solution near its temperature 39°Ð¡ was found. This temperature corresponds to the temperature of human organism upon a number of pathological states connected with inflammatory processes. The discovered effect can be used in the development of novel non-invasive methods of disease diagnostics.

Monitoring of brightness temperature of suspension of follicular thyroid carcinoma cells in SHF range by radiothermometry.

The purpose: The purpose of this research consisted in monitoring of brightness temperature of the suspension of follicular thyroid carcinoma cells during the necrosis of these cells in superhigh frequency (SHF) range. Methods: The monitoring of the change in the ratio between brightness temperatures TSHF and TIR values during the necrosis of these cells. The object of study was follicular thyroid carcinoma cells suspension prepared with use of Versene solution and 0.25% trypsin solution. The cells were precipitated by centrifugation and re-suspended in culture medium. The measurements of brightness temperatures were carried out with use of radiothermoimeter. SHF range was 3.4-4.2 GHz, and infrared (IR) range was 8-13 mm. The temperature of the suspension was maintained at 37.5°Ð¡. Results: It was found that upon the necrosis in the suspension of cells, an increase in brightness temperature in 3.4-4.2 GHz range (SHF range) occurs, while brightness temperature of the medium in the IR range does not change. Conclusion: The monitoring of necrosis of follicular thyroid carcinoma cells was carried out by SHF-radiothermometry. It was shown that during the necrosis the change of non-equilibrium state of cell medium occurs, that results in the change in the ratio between TSHF and TIR. During the necrosis, the brightness temperature in SHF range (TSHF) increases.

[Microwave emission from water in bioanalytical systems].

Mechanical stimulation of aqueous protein solution was found to be accompanied by electromagnetic radiation in the superhigh frequency range. This radiation was observed at solution temperatures near the phase transitions of water. This effect may occur in various bioanalytical systems, associated with injection of aqueous solutions in these systems, and may have impact on the results of bioalytical measurements. The discovered effect of generation of nonequilibrium microwave emission of water medium (which is the main component of the organism) in the 38-39°C temperature range, i.e. in the range of elevated temperature of the organism (which accompanies pathological condition in humans upon inflammatory diseases, i.e., infactious etc.) may be used for development of new non-invasive methods of disease diagnostics.