Calibration method of gas analyser detectors, and device for realisation thereof

FIELD: instrument engineering.

SUBSTANCE: invention is designed for calibrating gas analyser detectors, according to which there prepared is calibration substance solution with concentration A=By/k (%) as per Henry constant value k (mg/m %) at calibration temperature and as per the specified value of calibration substance mass concentration in calibration steam/gas mixture By (mg/m). After the solution has been introduced into the vessel in quantity enough for fully saturated equilibrium calibration steam/gas mixture to appear above the solution surface, the sensor calibration is carried out by means of mixture; at that, mixture concentration is changed by means of direct proportional change of solution concentration by diluting concentrated reference solution of calibration substance with analytical accuracy up to the specified concentration value A (%). There also proposed is the device for realising this method, which includes a solution point for preparing calibration solution with analytical accuracy, vessel with thermostatic device for obtaining steam/gas mixture with constant concentration corresponding to Henry law; at that, solution point includes graduated dose metre, graduated diluter, mixer with a reducer, capacity with solvent, and reference container with reference solution, which is stabilised with a gate valve meant for multiple use of container, and vessel with thermostatic device consists of thermometre and heat-insulating cover plate with an inlet branch pipe containing a normally closed return valve and a pusher for valve opening.

EFFECT: decrease of calibration substance losses; accuracy and reproducibility of metrological performance, and meeting requirements of industrial and ecological safety.

6 cl, 2 dwg

 

The invention relates to the field of gas analysis instrumentation and can be used when testing the performance and calibration of gas analyzers.

The invention is intended for preparation of calibration gas mixtures with a low content of vapors of volatile substances, mainly ammonia and other substances soluble in liquids and forming by evaporation of the calibration gas mixture for the subsequent calibration of gas analyzers.

There is a method of calibration of the detectors of the detector, whereby the preparation of calibration gas mixtures is carried out by passing the gas through free from the liquid space of the vessel, partially filled with the liquid substance, and changes in the concentration of vapor in the gas due to changes in gas flow, in which the substance is placed in a container in the form of its solution, and the concentration of vapor of the substance in the gas additionally change by changing the concentration of the substance in the solution (patent RF № 2181201, 7 G01N 30/00).

The disadvantage of this method is that when the open mouth of the vessel, the Henry's law is not respected. In the preparation of a mixture of internally carried out without complying with the proportions when mixing the components.

A device for the calibration of the detector containing the vessel on which ysenia gas pairs substances, gas line for supplying gas into the vessel, a device for dilution of the gas mixture, gas line for output of gas-steam mixture, the booster natural gas flow detector (RF patent No. 2145083, 7 G01N 30/04, 30/12, 1998).

A disadvantage of the known device is a big lag when entering the stationary modes, constant release of toxic substances from the device, lack of stability and limit the accuracy of the detector-detector, the complete dependence of the concentration of the mixture from the uncontrolled state devices for dilution and, as a consequence, the impossibility of metrological characteristics of the device to the detector - detector.

The closest in technical essence to the proposed method the calibration of the detector and the device for its implementation is the way (catalogue company Drager Sicherheitstechnik GmbH, prospect Ampoule with a calibration gas", ed. 4, 1993), according to which prepare the calibration solution containing the calibration substance in the solvent, and by exemplary capsules enter it into the closed vessel in a minimally sufficient amount of vapor of the substance in the vessel, forming a calibration gas mixture with a mass concentration By (mg/m3), corresponding to a given value required for calibration of the detectors, with the holding of the connecting pipes, separately attached to the vessel and to calibrate the diffusion detector and a flow-through detector, containing the booster gas flow.

A device for implementing the known method (catalogue company Drager Sicherheitstechnik GmbH, prospect Ampoule with a calibration gas", ed. 4, 1993) contains an exemplary ampoule with a calibration substance in the solvent vessel equipped with inlet and outlet nozzles and dispenser for discharging an exemplary sealed in the vessel, and in turn attached to the vessel diffusion detector with connecting pipe and a flow detector with pump gas flow with hoses containing the connection Spigots.

A disadvantage of the known method and device for calibrating the sensor detector is the fact that the calibration procedure is complex, time-consuming and costly, as due to the adsorption of the substance in the gas circuit is necessary to use at least three vials to obtain matching results, and calibration with other concentrations that differ from indicated on the vial, impossible.

The invention consisted in the development of such a method and device for the calibration of the detector, which allow a given concentration value of the calibration gas mixture in the vessel to produce in a single act the calibration of the detectors are suitable the m calibration solution, without loss of calibration substances and quantity in the vessel. When this task was to use the main feature of Henry's law about one correspondence between the concentrations of volatiles in the solution and above the solution. Namely, that the depot volatile substances in a solution volume significantly exceeds the required amount for complete saturation equal volume of gas above the solution. The excess equal to the coefficient of absorption of Oswald toabout. If the air temperature is 20°C for water-ammonia solution toabout=170. Therefore, the objective of the invention included to reinforce dominant and the stabilizing effect of Henry's law by reducing weathering, adsorption and other losses calibration substances, increasing the ratio of solution volume to the volume of gas-steam mixture, refining the Henry's law constant, temperature stabilization, the concentration of gas-steam mixture at the stability and reproducibility of the metrological characteristics and meet the requirements of industrial and environmental safety.

This task is accomplished by the fact that the calibration solution is injected through capping, stabilize the temperature of the vessel, liquid media and products involved in the calibration of the sensors, exposure indoors to equalize their temperature to the room temperature, and the ZAT is, at the steady state temperature of liquid media, thermostatic in unit temperature control vessel and a liquid medium involved in the calibration, and the steady-state temperature value in the temperature control device to determine a calibration substance-valued Henry's law constant and the concentration value of the calibration solution A (%) according to Henry's law, A=Wu/K for a given value of the mass concentration of the calibration gas mixture By (mg/m3), where K(mg/% m) Henry's law constant, prepared with analytical precision and injected into the vessel specified calibration solution in a quantity sufficient to education mirrors the calibration solution in the vessel mainly more than half of its capacity, and form on the solution of the calibration gas mixture, and then hermetically attaching the diffusion detector to the vessel, attach the gas cavity of the detector to the mirror calibration solution vessel and reproducibly stably and completely saturating the gas cavity detector calibration substance through the mirror calibration solution vessel in accordance with the action of Henry's law to the concentration By, to calibrate the detector, and a flow detector attached input and output to separate points of the vessel and forming a closed gas circuit, connecting the circuit to the mirror to lebowakgomo solution vessel, repeatedly move the contents of the path above the mirror calibration solution vessel through the pump gas flow and, consistently reproducible and fully saturating gas loop calibration substance through the mirror calibration solution vessel to concentration By in accordance with law Henry, calibrate the detector and the calibration of the detectors at other specified concentrations, while changing the concentration of the substance in the calibration gas mixture produced by varying the concentration of the calibration solution in the vessel according to Henry's law.

Another distinctive feature of the proposed method is that in exemplary capping impose concentrated standard solution calibration substance with a concentration that is installed with analytical precision, close the solution in the capping liquid shutter of an impermeable substance, neutral solution and its components, and close the bottles sealed with a cork, and then repeatedly use the exemplary closure for the preparation of calibration solutions, including solutions of different concentration.

The next distinctive feature of the proposed method is that to obtain a calibration solution with a concentration that is installed with analytical precision, dilute dose of kontsentrirovano the th sample solution solvent to the concentration A (%), installed according to Henry's law at a given mass concentration of calibration gas mixtures By (mg/m3), namely, the move from an exemplary capping dimensional dosing the dose of 1 l prepared calibration solutions (Wasabisabi, Seahaven. Brief chemical Handbook. L., "Chemistry", Len. div., 1991, s, 305-306) M(ml):

,

where M is the dose of a sample solution in 1 liter of prepared calibration solution, ml;

And mass concentration of the calibration solution, %;

ρ' is the density of a sample solution, g/cm3;

ρ is the density of the calibration solution, g/cm3,

in measuring the diluent containing a quantity of solvent, and increase the amount of solvent in measuring the diluent to the level of 1 l, and then move the entire contents of the diluent into the mixer, using the adapter faucet, close the faucet tube and mixing bring the calibration solution to a state of homogeneity and ready.

The problem is solved also by the fact that the proposed device for the calibration of the detector containing exemplary capping with a calibration solution containing the calibration substance in the solvent vessel equipped with inlet and outlet nozzles and dispenser for discharging an exemplary sealed in the vessel, in turn recognize Jaimie to the vessel diffusion detector with connecting pipe and a flow detector with pump gas flow with hoses, containing the connecting pipes, characterized in that it contains a vessel for preparation of calibration gas mixtures with a concentration of calibration solution, installed by Henry's law, with an analytical precision of the temperature control device for stabilizing the temperature and concentration of the calibration solution and gas mixture in the vessel, mud room for the preparation and stabilization of the calibration solutions of various concentrations with established analytical precision through exemplary capping.

Another distinctive feature of the device is that the inlet and outlet pipes of the vessel is installed on the insulating cover of the vessel, the inlet pipe includes a tube and an exhaust tube contains a normally closed check valve and plunger to open the valve, the vessel is inserted in the device temperature, containing a thermostatic fluid, and contains a thermometer.

The following distinctive feature of the device is that the mortar site contains a measuring dispenser, a measuring diluent faucet with adapter, a container of solvent and exemplary closure sealed tube with concentrated solution of the calibration substance with a mass concentration, installed with analytical precision and stable shutter consisting of a liquid, Gasana oncemay and neutral solution and its components, reusable closure.

The above features of the proposed method and device for the calibration of the gas analyzer provides measurements over a wide concentration range with high accuracy due to stabilization of the gas-steam mixture by reducing losses of nutrients, increasing the ratio of solution volume to gas volume, temperature stabilization during the specification of the Henry's constants and metrological characteristics.

For example, when calibrating the ammonia gas analyzers at the maximum permissible concentrations from 20 to 1500 mg/m3when the temperature T=293 K uncertainty in the temperature when the temperature deviation ΔT=±0.5°C,

analytical error in the solution concentration of 10% NH3in H2O by pharmacopeial article FSP-0410-5241-04 - γp=±1,0%; error dispenser-pipette 10 ml of GOST 29227-91 - γp=±1,0%; the accuracy of the mixing pump 1 l GOST 1770-74 - γm=±0,08%.

As a result, the calibration error according to GOST 12.1.016-79

when the factor of 1.1 with confidence probability P=95%, less than the error of the prototype ±5.0% and the error detector is ±20%.

This simplifies the operation, one filling is sufficient for the calibration of multiple sensors, multiple calibration toxic the substances remain in the vessel, what contributes to industrial and environmental safety. The stability and reproducibility of the metrological characteristics guaranteed by the validity of Henry's law, the procedure of the proposed method and device for its implementation.

The invention is illustrated by figure 1, which presents a view of the proposed device in section, and the scheme presented in figure 2.

The device comprises a receptacle I to obtain a calibration gas mixtures corresponding to Henry's law. The vessel 1 contains a cover 2. The cover 2 has a thermal insulation and a hole for a thermometer 3, the inlet pipe 4 and outlet pipe 5, the cover 2. The cover 2 has a thermal insulation and a hole for a thermometer 3, the inlet pipe 4 and outlet pipe 5 located inside the vessel 2. The inlet pipe 4 is supplied by the adapter 6 and the tube 7. The inlet pipe 5 contains the adapter 8, normally closed check valve 9 and the plunger 10. The vessel 2 is set in the temperature control device 11 containing thermostat 12 to accommodate a thermostatic fluid and insulated container 13 and closed with a total cover 14 made of an insulating material with a hole for thermometer 3. Diffusion detector 15 has a connecting pipe 16, and a flow detector 17 includes a booster gas flow 18 with hoses 19, 20 and connecting p the tubes 21 and 22.

The structure of the device includes a mud room for the preparation of solutions, corresponding to Henry's law, containing a measuring dispenser (not shown), measuring the diluent 23, a mixer 24 with the adapter 25 and exemplary closure (not shown), with a concentrated exemplary solution of the calibration substance analytical precision, with stopper and sealed with a cork.

In accordance with the proposed method is described device operates as follows. Stabilize the temperature of the vessel 1, thermostatic liquid tank with a solvent (not shown), the temperature control device 11, separately thermostat 12 and insulated container 13 and elements mortar site exposure indoors to equalize their temperature to the room temperature and the steady-state temperature in thermostatic fluid in the vessel with the solvent set thermostat 12 in insulated container 13, fill up thermostat 12 thermostatic liquid and set the vessel 1 in thermostat 12 is determined by the steady-state temperature in the temperature control device 11 known value of the Henry's law constant (for example, 5,65·103mg/m3%ammonia in distilled water at 20°C) and concentration of the calibration solution a=b/(a=500/5,65·103=0,0885%) for a given value of the mass concentration of Caleb ovocny gas mixture By (500 mg/m 3, MAC) and prepare a calibration solution with a concentration of As, selecting a measuring dispenser (pipette 10 ml GOST 29227-91) of the exemplary capping the dose of M (M=9.15, with ml when K=10,1% quality passport FSP-0410-5211-04 and tabular values R'=0,958 g/cm, p=is 0.998 g/cm) concentrated solution of the calibration substance with established analytical error, a dose in measuring the diluent 23 (dipstick 1 l GOST 1770-74)containing a certain amount of solvent (distilled water)and solvent diluted mixture to the level of 1 l dimensional diluent 23, and then attached in a vertical position on top of the mixer 24 (bottle BT-III-1-25-PET-PS-1,5 GOST R 51760-2001) with adapter 25 to the measuring diluent 23 and by changing their vertical position on mutually opposite, pour the solution into the mixer 24 and closing the mixer 24 with the adapter 25 is sealed by a stopper (not shown), stirred calibration solution and opening the tube, tightly attach the mixer 24 of the adapter 25 to the nozzle 4 of the vessel 1 and enter the calibration solution in the vessel 1 in a quantity sufficient for the formation of mirrors the calibration solution in the vessel 1 is mainly more than half of its capacity, and then adding diffusion detector 15 to the vessel 1, which is tightly inserted into the socket 16 recessed in the vessel 1 socket adapter 8 and opening the normally closed is LAPAN 9 pusher 10, join free of vapor of the substance space of the socket 16 of the detector 15 to the mirror calibration solution vessel 1, stably and reproducibly fully saturate this space pairs of substances through the mirror calibration solution vessel 1 to a constant preset mass concentration calibration gas mixture and to calibrate the detector 15, and a flow detector 17 with the pump gas flow 18 sequentially attached to the mirror calibration solution vessel 1 hoses 19 and 20, the connecting pipes 21 and 22 and the nozzles 4 and 5 form a closed gas circuit consisting of elements 5, 22, 19, 17, 19, 20, 21 and 4, and then, consistently, reproducibly and completely saturating the gas loop calibration substance with multiple forced circulation of gas in the circuit above the mirror calibration solution in the vessel 1 during the operation of the booster gas 18, calibrate the detector 17.

The device provides a calibration of ammonia gas analyzers in the whole range of toxic concentrations from 20 to 1500 mg/m3.

1. A method of calibrating the detectors of the detector, whereby to prepare the calibration solution containing the calibration substance in the solvent, which is injected into the closed vessel in a minimally sufficient amount of vapor of the substance in the vessel, forming kalibrovochno the gas mixture, with the mass concentration of By(mg/m3), corresponding to a given value, necessary for the calibration of detectors containing connective pipes, separately attached to the vessel and to calibrate the diffusion detector and a flow-through detector, containing the booster gas flow, characterized in that the calibration solution is injected through capping, stabilize the temperature of the vessel, liquid media and products involved in the calibration of the sensors, exposure indoors to equalize their temperature to the room temperature, and then at the steady state temperature of liquid media thermostatic in unit temperature control vessel and a liquid medium involved in the calibration, and the steady-state temperature value in the temperature control device to determine the calibration substances table the value of Henry's law constant and the concentration value of the calibration solution A (%) according to Henry's law a=by/K, for a given value of the mass concentration of the calibration gas mixture By(mg/m3), where K (mg/% m3- Henry's law constant, is prepared and injected into the vessel specified calibration solution in a quantity sufficient to education mirrors the calibration solution in the vessel mainly more than half of its capacity, and form on the solution of the calibration gas is mesh, and then, tightly attaching the diffusion detector to the vessel, attach the gas cavity of the detector to the mirror calibration solution vessel and reproducibly stably and completely saturating the gas cavity detector calibration substance through the mirror calibration solution vessel in accordance with the action of Henry's law to the concentration of By, calibrate the detector, and a flow detector attached input and output to separate points of the vessel and forming a closed gas circuit, connecting the circuit to the mirror calibration solution vessel, repeatedly move the contents of the path above the mirror calibration solution vessel through the pump gas flow and, consistently reproducible and fully saturating gas loop calibration substance through the mirror calibration solution vessel to the concentration of Byin accordance with the action of Henry's law, to calibrate the detector and the calibration of the detectors at other concentrations, to change a given matter concentration in the calibration gas mixture produced by direct proportional changes in the concentration of the calibration solution in the vessel according to Henry's law.

2. The method according to claim 1, characterized in that in the exemplary closure impose concentrated exemplary calibration races is a thief with a concentration installed with analytical precision, close the solution in the capping liquid shutter of an impermeable substance, neutral solution and its components, and close the closure sealed tube, made of a soft elastic material, and then repeatedly use the exemplary closure for the preparation of calibration solutions, including solutions of different concentration.

3. The method according to claim 1 or 2, characterized in that for obtaining an exemplary calibration solution with a concentration that is installed with analytical precision, diluted dose of a sample solution with a solvent to a concentration of As (%)installed according to Henry's law at a given mass concentration of the calibration gas mixture By(mg/m3).

4. A device for the calibration of the detector containing exemplary capping with a calibration solution containing the calibration substance in the solvent vessel equipped with inlet and outlet nozzles and dispenser for discharging an exemplary sealed in the vessel, and in turn attached to the vessel diffusion detector with connecting pipe and a flow detector with pump gas flow with hoses containing the connecting pipes, characterized in that it contains a vessel for preparation of calibration gas is aravich mixtures with concentration calibration solution, installed by Henry's law, with an analytical precision of the temperature control device for stabilizing the temperature and concentration of the calibration solution and gas mixture in the vessel, mud room for the preparation and stabilization of the calibration solutions of different concentrations installed with analytical precision through exemplary capping.

5. The device according to claim 4, characterized in that the inlet and outlet pipes of the vessel is installed on the insulating cover of the vessel, the inlet pipe includes a tube and an exhaust tube contains a normally closed check valve and plunger to open the valve, the vessel is inserted in the device temperature, containing a thermostatic fluid, and contains a thermometer.

6. The device according to claim 4, characterized in that the mortar site contains a measuring dispenser, a measuring diluent faucet with adapter, a container of solvent and exemplary closure sealed tube with concentrated exemplary calibration solution with a concentration that is installed with analytical precision and stable shutter consisting of liquid, gas-tight and neutral solution and its components, for reuse capping.



 

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FIELD: instrument engineering.

SUBSTANCE: device for generating flow of vapor-gas mixture with preset concentration of vapor has vessel partially filled with fluid, second vessel provided with branch pipes for supply and removal of gas, and vapors of fluid pipeline-leak. One of vessels is connected with gas discharge forcer; fluid vapors pipeline-leak connects both vessels. Vessel, partially filled with fluid, is mounted inside second vessel. Pipeline-line, connecting both vessels, is totally placed inside second vessel. Device is also provided with additional discharge forcer for adjusting concentration of fluid vapor in second vessel. Granulated filler is introduced into vessel partially filled with fluid. Device is also provided with gas analyzer for providing gas concentration in space of second vessel.

EFFECT: higher precision of keeping of preset concentration of vapor; improved efficiency of vapor concentration control and adjustment.

FIELD: chemical technology.

SUBSTANCE: invention relates to a method for synthesis of ester perfluorinated derivative by using a chemical reaction. This reaction represents the fluorination reaction of the parent compound as a raw, the reaction of chemical conversion of fragment of ester perfluorinated derivative to yield another ester perfluorinated derivative or the interaction reaction of carboxylic acid with alcohol under condition that at least one or reagent, i. e. carboxylic acid or alcohol, represents a perfluorinated compound wherein indicated perfluorinated derivative of ester represents a compound comprising a fragment of the formula (1):

with a boiling point 400°C, not above. The reaction time for carrying out abovementioned chemical reaction is sufficient to provide the required yield of ester perfluorinated derivative and wherein this yield of ester perfluorinated compound is determined by the gas chromatography method by using a nonpolar column. Also, invention relates to a method for pyrolysis of ester perfluorinated derivative with a boiling point 400°C, not above, to yield the dissociation product wherein this product represents a derivative of acyl fluoride or ketone and wherein pyrolysis time is sufficient to provide the required degree of conversion of ester perfluorinated derivative and wherein the indicated conversion degree of ester perfluorinated derivative is determined by gas chromatography method by using a nonpolar column. Also, invention relates to a method for analysis of ester perfluorinated derivative with a boiling point 400°C, not above, that involves analysis of ester perfluorinated derivative in a sample containing ester perfluorinated derivative by gas chromatography method by using a nonpolar column wherein ester perfluorinated derivative represents compound comprising a fragment of above given formula (1).

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with a boiling point 400°C, not above. The reaction time for carrying out abovementioned chemical reaction is sufficient to provide the required yield of ester perfluorinated derivative and wherein this yield of ester perfluorinated compound is determined by the gas chromatography method by using a nonpolar column. Also, invention relates to a method for pyrolysis of ester perfluorinated derivative with a boiling point 400°C, not above, to yield the dissociation product wherein this product represents a derivative of acyl fluoride or ketone and wherein pyrolysis time is sufficient to provide the required degree of conversion of ester perfluorinated derivative and wherein the indicated conversion degree of ester perfluorinated derivative is determined by gas chromatography method by using a nonpolar column. Also, invention relates to a method for analysis of ester perfluorinated derivative with a boiling point 400°C, not above, that involves analysis of ester perfluorinated derivative in a sample containing ester perfluorinated derivative by gas chromatography method by using a nonpolar column wherein ester perfluorinated derivative represents compound comprising a fragment of above given formula (1).

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FIELD: chemistry.

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FIELD: medicine.

SUBSTANCE: each blood sample is analysed twice. A fresh blood sample is centrifuged at 2,000 rpm for 5 min. The samples are separated in plasma fractions and formed elements. A solid-phase plasma extraction is performed by sequential passing of 100% acetonitrile, plasma, distilled water, 50% acetonitrile solution under vacuum through a cartridge with Oasis HLB 3 cc sorbent. The cartridge with the sorbent is dried under vacuum, and 100% methylene chloride is passed through the sorbent. An aliquot portion of the produced extract is chromatographed. Producing the extract of formed elements is ensured by dispersed solid-phase extraction: by adding 100% acetonitrile thereto and agitating intensively. That is followed by adding a number of QuECHeRS salts for extraction, agitating, centrifuging for 10 minutes at 2,000 rpm; that is accompanying by forming 3 layers; an upper layer is transferred to another test tube, which contains a number of QuECHeRS salts for purification; the layers are centrifuged at 2,000 rpm; the upper layer is sampled. Plasma and formed elements extracts are analysed by Agilent 1200 liquid chromatograph with a fluorimetric detector on Zorbax column 50 mm long and having an inner diameter of 4.6 mm with Eclipse PAH C18 sorbent at column temperature 27°C; a movable phase is presented by mixed acetonitrile and water at flow rate 1.5 cm3/min and optimising elution in the gradient mode (supplying the movable phase of 60 vl % to 68 vl % of acetonitrile for 1 min, increasing 60 vl % to 68 vl % of acetonitrile for 3 min, increasing 68 vl % to 70 vl % for 0.5 min, increasing acetonitrile 70 vl % to 90 vl % for 1.5 min, increasing acetonitrile 90 vl % to 100 vl % for 4.5 min, supplying 100% acetonitrile for 1.5 min, reducing acetonitrile to 60 vl % and supplying 60% acetonitrile for 4 min to balance the column). An excitation wavelength of the fluorimetric detector makes 265 nm, and an emission wavelength makes 412 nm. A calibration chart is used to quantify benz(a)pyrene in plasma and formed elements separately, while the results are summed up.

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3 cl, 6 tbl, 1 ex

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to experimental pharmacology, and can be used for quantitative determination of carnosine in tissues and physiological liquids. Determination of carnosine in biological materials is carried out by highly-selective mass spectrometry method using electrospray ionization. At that, deproteinization of blood plasma should be preliminary carried out using 10 % aqueous solution of trichloroacetic acid. Then aliquot of internal standard solution of L-alanyl-carnosine is added to deproteinizated sample. And separation of extraction products is performed at reversed-phase chromatographic column 4.6×150 mm with temperature separation of 35 °C and eluent feed rate 0.7 ml/min. Used eluent is 10 mM ammonium acetate, acidified with glacial acetic acid to pH 3.7, and mixture of acetonitrile with 10 mM ammonium acetate in ratio of 90:10, taken in ratio of 10:90, respectively. Detection of carnosine is carried out by four child ions with m/z 110.0, 156.1, 180.0, 210.1, formed as result of molecular ion carnosine disintegration with m/z 227.1. Concentration of carnosine is calculated by chromatographic peak carnosine area relation to L-alanyl-carnosine internal standard peak area.

EFFECT: invention provides highly selective and sensitive gas chromatography/mass-spectrometric method for quantitative determination of carnosine in biological substrates.

1 cl, 6 dwg, 2 tbl, 1 ex

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