METHOD OF DETERMINING N-(4-NITRO-2-PHENOXYPHENYL)-METHANESULPHONAMIDE IN BIOLOGICAL MATERIAL Russian patent published in 2014 - IPC G01N33/50 G01N30/86 

FIELD: chemistry.

SUBSTANCE: invention relates to biology and toxicological chemistry and can be used in chemical-toxicology, expert forensic and clinical laboratories. The method includes: crushing a biological object containing N-(4-nitro-2-phenoxyphenyl)-methanesulphonamide, settling twice for 45 minutes with portions of an organic isolating agent which is methyl acetate, combining the obtained extracts, evaporating the solvent from the resultant extract, treating the residue with acetone, separating the acetone extract, evaporating the solvent from resultant extract, dissolving the residue in diethyl ether, extracting the ether solution with a buffer solution at pH 9-10, acidifying the aqueous alkaline extract with 24% hydrochloric acid to pH 2-3, saturating the obtained solution with sodium bromide, extracting with ethyl acetate, evaporating the obtained extract in an air current at 20-22°C until a dry residue is obtained, dissolving the residue in a mixture of hexane and acetone taken in volume ratio of 8:2, performing chromatography on a macrocolumn with silica gel L 40/100 mcm using a hexane-acetone mobile phase in volume ratio of 8:2, combining eluate fractions containing the analysed substance, evaporating the eluent in an air current at 20-22°C until complete removal of the solvent, dissolving the residue in methanol and performing determination via a combined physical-chemical method in the form of chromatography-mass spectrometry, using a DB-5 MS EVIDEX capillary column with a mobile phase which is 5% phenyl-95% methylpolysiloxane, using a mass-selective detector operating in electron impact mode, the initial thermostat temperature of the column is 70°C, maintaining said temperature for 3 minutes, further raising the temperature from 70°C to 290°C at a rate of 20°C per minute, maintaining the final temperature of the column for 16 minutes, the temperature of the injector is 250°C, the temperature of the quadrupole is 150°C, the temperature of the detector interface is 300°C, detecting strength of the signal resulting from charged particles formed when bombarding the analysed substance coming from the capillary column and falling into an ion source with an ionising electron beam with energy of 70 eV, recording the mass spectrum on the full ion current, while calculating the amount of N-(4-nitro-2-phenoxyphenyl)-methanesulphonamide from the area of the chromatographic peak.

EFFECT: high sensitivity of analysis.

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