This work demonstrates the use of a solid-state nanopore detector to monitor the activity of a single molecule of a model enzyme, horseradish peroxidase (HRP). This detector includes a measuring cell, which is divided into cis- and trans- chambers by a silicon nitride chip (SiN structure) with a nanopore of 5 nm in diameter. To entrap a single HRP molecule into the nanopore, an electrode had been placed into the cis-chamber; HRP solution was added into this chamber after application of a negative voltage.
View Article and Find Full Text PDFThe review considers modern achievements and prospects of using nanowire biosensors, principles of their operation, methods of fabrication, and the influence of the Debye effect, which plays a key role in improving the biosensor characteristics. Special attention is paid to the practical application of such biosensors for the detection of a variety of biomolecules, demonstrating their capabilities and potential in the detection of a wide range of biomarkers of various diseases. Nanowire biosensors also show excellent results in such areas as early disease diagnostics, patient health monitoring, and personalized medicine due to their high sensitivity and specificity.
View Article and Find Full Text PDFThe review considers the possibility of using atomic force microscopy (AFM) as a basic method for protein detection in solutions with low protein concentrations. The demand for new bioanalytical approaches is determined by the problem of insufficient sensitivity of systems used in routine practice for protein detection. Special attention is paid to demonstration of the use in bioanalysis of a combination of AFM and fishing methods as an approach of concentrating biomolecules from a large volume of the analyzed solution on a small surface area.
View Article and Find Full Text PDFA new approach for modifying electrodes using porous membranes based on anodic aluminum oxide with pore diameters of 0.1 and 0.2 µm and a membrane-like substance didodecyldimethylammonium bromide (DDAB) was proposed to study the electrocatalytic efficiency of the system.
View Article and Find Full Text PDFComparative mass spectrometric analysis of protein composition was carried out in 36 blood plasma specimens from patients with renal cell carcinoma and 20 specimens from donors. Analysis of protein composition of plasma specimens devoid of the major protein fractions showed a 20-50% higher level of protein identifications in patient' specimens. Specimens of the control and experimental series were similar by protein composition, 70-80% identifications in experimental and control series coinciding.
View Article and Find Full Text PDFPatol Fiziol Eksp Ter
December 2017
The purpose of the research consisted in detection of fluctuation of brightness temperature (TSHF) of water in the area of the temperature Т = 42°С (that is critical for human) during its evaporation by SHF radiometry. Methods: Monitoring of the changes in brightness temperature of water in superhigh frequency (SHF) range (3.8-4.
View Article and Find Full Text PDFThe 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.
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).
View Article and Find Full Text PDFUnlabelled: 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°С. The measurements of brightness temperatures were carried out with use of radiothermometer.
Biochem Biophys Rep
September 2016
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 НО was employed. Microwave emission measurements were carried out in the 3.
View Article and Find Full Text PDFMechanical 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.
View Article and Find Full Text PDFA method for detection and identification of the hepatitis C virus antigen (HCVcoreAg) in human serum with consideration for possible amino acid substitutions is proposed. The method is based on a combination of biospecific capturing and concentrating of the target protein on the surface of the chip for atomic force microscope (AFM chip) with subsequent protein identification by tandem mass spectrometric (MS/MS) analysis. Biospecific AFM-capturing of viral particles containing HCVcoreAg from serum samples was performed by use of AFM chips with monoclonal antibodies (anti-HCVcore) covalently immobilized on the surface.
View Article and Find Full Text PDFPatol Fiziol Eksp Ter
December 2017
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-insulator» structures. For the biospecific detection of target protein, the NW surface was modified with aptamers against the target protein.
View Article and Find Full Text PDFMicrowave radiation at 3.4-4.2 GHz frequency of the cytochrome P450 CYP102 A1 (BM3) solution was registered during the lauric acid hydroxylation reaction.
View Article and Find Full Text PDFThe nanowire (NW) detection is one of fast-acting and high-sensitive methods allowing to reveal potentially relevant protein molecules. A NW biosensor based on the silicon-on-insulator (SOI)-structures was used for biospecific label-free detection of NFAT 1 (D-NFAT 1) oncomarker in real time. For this purpose, SOI-nanowires (NWs) were modified with aptamers against NFAT 1 used as molecular probes.
View Article and Find Full Text PDFA method of atomic force microscopy-based fishing (AFM fishing) has been developed for protein detection in the analyte solution using a chip with an immobilized aptamer. This method is based on the biospecific fishing of a target protein from a bulk solution onto the small AFM chip area with the immobilized aptamer to this protein used as the molecular probe. Such aptamer-based approach allows to increase an AFM image contrast compared to the antibody-based approach.
View Article and Find Full Text PDFAchievement of the concentration detection limit for proteins at the level of the reverse Avogadro number determines the modern development of proteomics. In this review, the possibility of approximating the reverse Avogadro number by using nanotechnological methods (AFM-based fishing with mechanical and electrical stimulation, nanowire detectors, and other methods) are discussed. The ability of AFM to detect, count, visualize and characterize physico-chemical properties of proteins at concentrations up to 10(-17)-10(-18) M is demonstrated.
View Article and Find Full Text PDFAtomic force microscopy (AFM) allows to visualize and count the individual protein molecules and their complexes within multiprotein systems. On the other hand, optical biosensor (OB) provides information on complex formation kinetics as well as complex lifetime (τ(LT)) and affinity. Comparison of complex lifetime τ(LT) with the time required for enzyme's catalytic cycle (τ(cat)) enables to characterize productive complexes and distinguish them from non-productive ones.
View Article and Find Full Text PDFThe review is concerned with the state-of-the-art and the prospects of development of nanotechnologies in clinical proteomics. Nanotechnology in clinical proteomics is a new medical research direction, dealing with the creation and application of nanodevices for performing proteomic analyses in the clinic. Nanotechnological progress in the field of atomic force microscopy makes it possible to perform clinical studies on the revelation, visualization and identification of protein disease markers, in particular of those with the sensitivity of 10(-17) M that surpasses by several orders the sensitivity of commonly adopted clinical methods.
View Article and Find Full Text PDFThe possibility of using the resonant mirror biosensor to detect point substitutions in oligonucleotides was demonstrated with a fragment of the Helicobacter pylori 23S rRNA gene, point mutations in which are responsible for clarythromycin resistance. Conditions were optimized for the interaction of a probe immobilized on the sensing surface with targets containing various nucleotide substitutions. A probe allowing reliable discrimination of mutant targets was selected.
View Article and Find Full Text PDFProtein-protein interactions form the proteinaceous network, which plays a central role in numerous processes in the cell. This review highlights the main structures, properties of contact surfaces, and forces involved in protein-protein interactions. The properties of protein contact surfaces depend on their functions.
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