PCR-based analysis techniques and method are discussed. The focus of this paper is on the comparison of different methods of PCR implementation (e.g. classical PCR, qPCR and digital PCR) and their analytical characteristics (sensitivity, specificity, reproducibility and others). One of the most crucial tendencies of development PCR-based devices is microchip technologies. They can provide a high automation level of analytical manipulations and a high level of detection sensitivity. The mathematical models of PCR basic processes are presented in the paper. Also, we discuss some current methods of medical diagnostics.

¹Institute for Analytical Instrumentation of RAS, Saint Petersburg
²Pavlov Institute of Physiology RAS, Saint-Petersburg

The paper describes possibilities of the domestic analytical station allowing to divide a mixture of peptides by HPLC on individual components, followed by mass spectrometric fragmentation of the separated peptides and to make stochastic identification of amino acid sequences basing on the proteome databases comparison. Station possibilities are demonstrated on the peptide analyses of human hemoglobin and human acetylcholine receptor fragments.

¹M.M. Schemyakin and Yu.A. Ovchinnikov Institute of bioorganic chemistry, RAS, Moscow
²Institute for Analytical Instrumentation of RAS, Saint-Petersburg

А method of PCR signal model characteristic investigation is discussed. It is based on sigmoid function and uses fixed change of fluorescence intensity during one or several temperature cycles (pulse disturbance). A comparison of pulse and noise disturbance was performed. The conclusion was made that it is suitable to use additional signals filtration and threshold method to reduce noise impact on PCR signals modeling. It was also explained why errors of threshold cycles measuring are reduced.

Institute for Analytical Instrumentation of RAS, Saint-Petersburg

The "Device for measuring intercellular potentials" consisting of the entrance amplifier, controller of connection with the computer and a power unit was developed and made in Institute for Biological Instrumentation of the Russian Academy of Sciences. The device has no handles; control is by the computer, which display shows all installations and results of measurement. The measuring device has high metrological characteristics - sensitivity, entrance resistance, low noise level, good protection against environmental disturbances, sufficient pass-band. Besides, the important parameters are simplicity of the adjustment, friendly users interface and availability of the device under the price.

Institute for Biological Instrumentation with Manufacturing Facilities of the RAS, Pushchino, Moscow region

Method of electrochemical measurements, a direct alternating-current coulometry, based on the principles of determination the coulometric constant of the electrochemical cell is proposed. This method significantly reduces analysis time compared to the previously known analogs. The possibility of determining the quinone and hydroquinone in aqueous solutions is shown. The values of coulometric constants of electrochemical cells for the different volumes of solution were found.

Saint-Petersburg State University

A possibility for obtaining monolith chromatographic columns based on quartz capillaries is studied using electron beam initiated in situ polymerization of the monomer mixture glycidyl methacrylate: methyl methacrylate: ethylene glycol dimethacrylate in the ratio 1:1:2 using formamide, propanol-1, n-decanol and 1,4-butanediol porogenic solvents in different concentrations. A uniform monolith column is only formed in the case of using formamide characterized by a small molecule size and inability to interact with the monomer molecules and growing polymer chains. The use of other solvents containing hydroxyl groups reacting with the monomer molecules and causing chain termination results in the incomplete capillary filling (in the case of propanol-1), loose inhomogeneous structure (in the case of 1,4-butanediol) or complete removal of the mixture from the capillary (in the case of n-decanol). Generally, optimal conditions are determined for in situ preparation of chromatographic capillary columns with reproducible characteristics due to the precise control of the electron beam initiation parameters.

¹Institute for Analytical Instrumentation of RAS, Saint-Petersburg
²Engineering Technology Center RADIANT, Saint-Petersburg
³Saint-Petersburg State University of Economics and Engineering

It is offered to use quadrupole collisional cell as a gas-dynamic interface for a creeping discharge (CD) ion source for elemental analysis of dielectrics. It will reduce the energy distribution width of the ions from the CD ion source and accommodate the source to use with low resolution mass-spectrometers. The width of ions energy distribution from CD ion source was experimentally estimated. The results of measurements were used for calculation model creation. By this model the electric fields and the energy distribution of ions were calculated, conditions which lead to energy distribution reduction to 2÷3 eV were found. The optimal mode of gas inlet to the collision cell and the parameters of high-frequency power supply were chosen.

Institute for Analytical Instrumentation of RAS, Saint-Petersburg

Possibility of improvement of, resolving ability and ion peak form is discussed in operation of a quadrupole mass-analyzer with low energy ions without prefilter application use. It was experimentally shown, that this is achieved by the increase under the certain law of velocity of ions input into the regional field inlet of a mass-analyzer with maintenance of ion initial working velocity in the mass-analyzer. Thus, for ions with mass 502 а.е.m. with the working energy 5 eV at the expense of these ions velocity rate input into the analyzer regional field approximately 2.5 times in comparison with working velocity the improvement of sensitivity made 360 % with maintenance of initial resolving ability, or resolving ability improvement approximately 2 times at maintenance of initial sensitivity with simultaneous improvement of ion peak shape in mass spectrums.

Institute for Analytical Instrumentation of RAS, Saint Petersburg

Discrimination level on masses in an analytical quadrupole mass-analyzer with prefilters for the levels of resolving ability equal R_0.1 = 1.5M, M, 0.75M, 0.5M was determined experimentally, within the range of mass number 31–426 а.е.m. Discrimination level on heavy masses was shown to decrease with the decrease of the resolving ability. For example, for ions with mass 426 а.е.m. in a mass spectrum of perfluorotributylamine the discrimination on masses decreases more than 10 times at transition from R_0.1 = 1.5M to R_0.1 = 0.5M. Comparison of levels of discrimination on masses in a quadrupole mass-analyzer with prefilters with the relative intensity of the same ionic peaks of the tabular mass spectrum was obtained on a magnetic mass-analyze.

Institute for Analytical Instrumentation of RAS, Saint-Petersburg

In this work a new method of monochromatization and formation of the ion beam produced by mass-spectrometer ion sources with a wide energy range distribution is proposed. The method is based on converting the ion energy spectrum by the electric field pulse shock on ions in nonuniform electric field. The proposed method is radically different from those based on the dissipation ion energy in the collision cells.

Institute for Analytical Instrumentation of RAS, Saint-Petersburg

The series of publications describes a new method to control the movement of the charged particles by high frequency electric fields. This new class of high frequency electric fields is characterized by pseudopotentials slowly evolving in time. The paper considers the time signals which can be characterized by "slow" and "fast" characteristic times. The universal representation for the signals with the spectra separated into narrow intervals with non-zero spectral function was obtained. Different technical approaches for the generation of such time signals are considered.

Institute for Analytical Instrumentation of RAS, Saint-Petersburg

The series of publications describes a new method to control the movement of the charged particles by high frequency electric fields. This new class of high frequency electric fields is characterized by pseudopotentials slowly evolving in time. New class of mass spectrometric devices for transport of charged particles is suggested using the developed general theory of pseudopotentials slowly evolving in time and high frequency electric fields with Archimedean properties. The paper considers various types of mass spectrometric devices and instruments which can be developed using these high frequency electric fields as a background. Some prototypes of these mass spectrometric devices are also discussed.

Institute for Analytical Instrumentation of RAS, Saint-Petersburg

Minimization functional procedure of the reverse task in the space of all parameters of the reflecting system (the semi-conductor substrate-transparent ultra-thin film) was developed. This allows to solve a number of problems. Rules of choice of initial significances of refractive index and quotient of absorption of the substrate for the first step of a method of consecutive approaching in the decision of an inverse problem become physically substantiated. Now due to the reliability of the developed procedure these initial values are naturally set on the point of the absolute minimum of the functional in complete space of parameters of the reflecting system. This ensures coordination of the initial values with the parameters of the film defined in the course of finding of an absolute minimum of the functional. At the same time it also means a complete coordination with the types of experimental errors. Definition of types of errors was added by new conditions on parameters value in the point of an absolute minimum functional. This allowed more precise classification of experimental errors. In this connection there is a possibility to define a degree of manifestation of mathematical incorrectness of reverse task depending on the size and type of experimental errors.

¹Sumy, Ukraine
²Institute for Analytical Instrumentation RAS, Saint-Petersburg

The structure and properties of nonlinear adaptive filter group (NAF) are considered. The filters are based on single neurons and on neural networks. The precision parameters — the upper level and mean absolute error of filters — are analyzed. Such NAF extend the class of stack filters and have better performance in noise suppression.

SPbSPU, Saint-Petersburg

Some versions of distortions arising at registration of distributions of time intervals within nanosecond range are discussed. Versions of their decrease are given. The variant of level distortions decrease is presented at impulse START imposing on the end of a signal INHIBITION. The algorithm of their interaction, technique of its realization is offered and the results its efficiency work test are presented.

¹State Institute of Nuclear Power Engineering of National Nuclear Scientific University "MIFI"
²State Scientific Center of Russian Federation "Institute for Physics and Power Engineering
named after A.I. Leypunskiy", Obninsk

Results of calculation of key parameters of the mirror-symmetric imposed measuring condenser are presented. For numerical 2D simulation of the integrated equations and mirror displays have been used. The surface of each electrode broke on two parallel parts. Such approach has simplified procedure of the numerical decision of a two-dimensional problem in comparison with application of standard final-element schemes. It allows to carry out calculation of electric fields of flat layered environments with smaller expenses. The program of numerical calculations is realized in MAPLE.

Vitebsk State Technological University

On the basis of a thermal type micro sensor the pilot model of the air mass flow meter for the automotive industry was developed and made. The design and the manufacturing technology of a micro sensor are described. The procedure and results of tests of the mass flow meter are presented.

¹Ural State University, Ekaterinburg
²Scientific and Production Association of Automatics named after academician N.A. Semikhatov, Ekaterinburg

Influence of a detector dead layer on the form of the calculated function the Si detector was evaluated. Within the range of energies lower than the energy of the registered radiance, a role of a dead layer of the detector and features of the form of function of the response of the detector are considered.

¹Irkutsk State University of Transport
²Applied Physics Institute at Irkutsk State University

The ambiguity of the definitions of "smart sensor" as a technical mean of measurement is revealed. Causes and consequences of differences in the representation of "smart sensor" as a transmitter were generalized. The main points of the international standard IEEE 1451 regarding classification of intelligent measuring instruments are presented. Data on the functionality of a fluxgate type sensor, which are used as "smart sensor" in the development of measurement and information technology, are presented.

Ufa State Aviation Technical University

DEVICES AND MEASURING METHODS FOR BIOCHEMISTRY

WORKS FOR MASS SPECTROMETRY

INSTRUMENT RESEARCHES AND WORKINGS OUT FOR DIFFERENT AREAS

Vol. 21 contents and the author's index >>