METHOD OF DETERMINING SUBSTITUTED 2-METHOXYHYDROXYBENZENE IN BIOLOGICAL MATERIAL Russian patent published in 2014 - IPC G01N33/50 G01N30/02 

FIELD: chemistry.

SUBSTANCE: invention relates to biology and toxicological chemistry and can be used in practice of sanitary and epidemiological stations, chemical-toxicological, forensic and veterinary laboratories. A biological material, containing substituted 2-methoxyhydroxybenzene, is two times (each time for 30 minutes) infused with ethylacetate with mixing, separate extracts are separated from solid particles of the biological material, combined, ethylacetate is evaporated in an air flow at 18-22°C, residue is repeatedly processed with acetone, acetone extracts are separated, combined, dehydrated, evaporated in an air flow at 18-22°C, and then in a nitrogen flow until a solvent is completely removed, residue is dissolved in hexane, extracted with a buffer solution with pH 12-13, a water-alkaline extraction is separated, acidified to pH 2-3, saturated with sodium sulphate, extracted with diethyl ether, the ether extract is separated, dehydrated, evaporated in an air flow at 18-22°C, and then - in a nitrogen flow until the solvent is completely removed, residue is dissolved in a mixture of solvents hexane-dioxane-propanol-2, taken in a ratio of 20:5:1 by volume, chromatographed in macrocolumn with silicagel KSS No 3 80/120 mcm with the application of a mobile phase hexane-dioxane-propanol-2 in a ratio of 20:5:1 by volume, eluate fractions, containing the analysed substance, are combined, the eluent is evaporated first in an air flow at a temperature of 18-22°C, and then in a nitrogen flow until the solvent is completely removed, residue is dissolved in dichloromethane, processed for 20 minutes with N-tert-butyl-dimethylsilyl-N-methyltrifluoroacetamide under conditions of heating at a temperature of 60°C with carrying out determination by a chromatography-mass spectrometry method with the application of a capillary column 25 m long with an internal diameter of 0.2 mm with an immobile phase (5%-phenyl)-methylpolysiloxane, with the application of a mass-selective detector, working in an electron impact mode, an initial temperature of the column thermostat constitutes 70°C, the said temperature is kept for 3 minutes, further the temperature is programmed from 70°C to 290°C at a rate of 20°C per minute, the final column temperature is kept for 10 minutes, the injector temperature constitutes 250°C, the quadrupole temperature is 150°C, the temperature of a ion source is 230°C, the temperature of the detector interface is 300°C, intensity of a signal, conditioned by charged particles, formed in the bombardment of the analysed substance, leaving the capillary column and getting into the ion source, with a ionising beam of electrons with the energy of 70 eV, is registered, the mass-spectrum by the complete ion flow is registered and an amount of substituted 2-methoxyhydroxybenzene is calculated by the area of a chromatographic peak of its trimethylsilyl derivative.

EFFECT: achievement of an increased analysis sensitivity.

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