CS264989B1 - Method of quantitative analysis trace amount content n-/1-formamide-2,2,2-trichloroethylene/morpholine in vegetable materials - Google Patents

Abstract

The invention and concerns the field of engineering, where the management of the body is mainly lateral torsion. For the purpose of reducing Sliding Sliding Guides Having the length and width of the leading Saw is presented a solution that reduces the unfavorable length ratio "L" to width "B" to the border g you creating a flip-flop system essentially one plane, at least one pair of flip-flops belong to the body and the other pair guided by the body They are.

Description

The invention relates to a method for the quantitative analysis of trace amounts of N- (1-formamido-2,2,2-trichloroethyl / morpholine / trimorphoramide) in plant materials.

N- (1-formamido-2,2,2-trichloroethyl) morpholine, known by the generic name trimorphamide, is the original Czechoslovak systemic fungicide (CS 193 659), which is formulated into a suitable dosage form for use in controlling powdery mildew on grape vine, barley , cucumbers, tobacco, apple trees, spewing plants and other cultures.

A rapid analytical procedure for the quantitative analysis of the active substance content with the required evidence and recovery is essential for the prompt assessment of the trimorphamide residue levels in treated cultures at harvest time as well as its biodegradation in individual environmental compartments. Gas chromatographic method for the determination of trimorphamide residues in these crops, used to date in the study of its residue dynamics (Kováč J .; Kovačičová J., Bátor V .: 5th International Congress on Pesticide Chemistry, Kyoto Japan, 20, 8-4. 1982, Vol. 4, 201-205. Pergamon Press, Oxford-New York-Toronto-Sydney-Paris-Frankfurt, 1983, Kovac J., Koprd V, Radiochem, Radional, Letters 33/3, 183-186. , (1987);

Kovac J., Gramblickova A., Minarova E., Kurucova M .: Agrochemistry 26/3, 88-90 (1986);

CS 254 674) is curious about the separation process of plant coextracts based on their partial separation in an unmixed organic solvent-water system and final purification by thin layer chromatography. The time required, in particular, in the long separation of the resulting emulsions at the organic solvent-water interface, as well as in the slow filtration of the aqueous phases during multiple extraction. In addition to the above, the processes are also demanding on the consumption of organic solvents of the desired analytical purity.

The above-mentioned drawbacks are eliminated by a method of quantitative analysis of trace amounts of N- (1-formamido-2,2,2-trichloroethyl) morpholine in plant materials by the gas chromatography method according to the invention, which consists in separating the disturbing coextracts on a silica column. the mobile phase is passed under pressure and the content of N- (1-formamido-2,2,2-trichloroethyl / norfoline) is evaluated in the concentrated fraction collected by the mobile phase by gas chromatography.

The process according to the invention does not require a complete, cost-effective and instrumental high-performance liquid chromatography apparatus, but only a high-pressure pump with a controlled flow of mobile phase connected via a dosing loop to the column is sufficient. The separation process is very efficient and fast, and solvent consumption is at least ten times lower than the methods used hitherto. The simplicity, speed and accuracy of the method of the invention predetermines it for use in serial analyzes of a large number of samples for trimorphamide content in biological substrates.

The following example illustrates the invention.

Example

Quantitative analysis of N- (1-formamido-2,2,2-trichloroethyl) morpholine (trimorphamide) in plant materials.

All the chemicals and solvents used were of analytical purity, and the solvents were distilled prior to use, leaving a one-third distillation residue based on the total volume of distilled solvent. The following equipment was used: electric homogenizer with coffee grinding attachment, dosing pump - liquid chromatograph accessory (another analogous dosing pump at least 6 MPa possible),, 3 dosing loop (50 mm), dosing syringe with blunt needle (100 mm), 40x4 mm pre-column with silica gel packing (30 pm), 2 x 150x3.2 mm packed with spherical silica gel (5 pm), connected in series, mobile phase: n-hexane: ethyl alcohol (92: 8 v / v) ), flow:

cm ³ .min ^-1 , pressure: 5.2 MPa, gas chromatograph packed column 10% diethylene glycol sukoinate on porous polymeric carrier of styrene-divinylbenzene (80/100) copolymer, detector

electron capture ≥ ³ Ni (250 ° C), carrier gas: argon - 60 cm ³ .min column temperature: 160 ° C, injector: 250 ° C, detector: 270 ° C.

After washing the chromatographic columns with mobile phase n-hexane / ethyl alcohol and equilibrating the conditions, the retention time of trimorphamide is determined as follows: a -3 chloroform solution of trimorphoramide Standard (conc. and eluted with the mobile phase using a pressure pump at a flow rate of 1 cm / min. The retention time of trimorphamide (12 min in this case) is determined by monitoring the trimorphamide content of the collected fractions (1 cm ³ ) of the effluent mobile phase by gas chromatography. At the same time, extracts can be prepared. To 25 g of homogenized plant material is added 100 cm ^{3 of} chloroform and extracted on a mechanical shaker in a 250 cm ³ flask with a cap for 15 minutes. 50 g of anhydrous sodium sulfate are then added and the mixture is shaken vigorously for a further 30 minutes. From the extract, pipette 5 cm ³ into a calibration vial and concentrate with a stream of air at a water temperature of 55 ° C to a volume of 1 cm ^J. From the concentrated chloroform extract of the sample, inject 50 mm onto a chromatography column and collect the mobile phase fraction corresponding to a time interval of 10.5 to 13.5 min (3 cm ³ ), into a 5 cm conical flask, at the end of the tapered, calibrated to a volume of 100 mm and closed by ground glass stopper. The collected fraction is concentrated to a volume of 100 cm ³ with a water bath (55 ° C), added with 3 cm ³ of ethyl acetate and concentrated again to a volume of 100 cm ³ .

From this solution, 5 mm is injected into a gas chromatograph. The trimorphamide content shall be determined by the absolute calibration method, by direct comparison of the wave heights of trimorphamide in the calibration solution and in the sample,

The yield of the method, verified on model experiments of fortified samples of cucumbers, barley, tobacco, apples, grape, green mass of barley leaves, was in the range of 80 to 90%, the limit of determination of the method is 0.05 mg.kg

Claims (1)

OBJECT OF THE INVENTION Method of quantitative analysis of trace amounts of N- (1-formamido-2,2,2-trichloroethyl) morpholine in plant materials by gas chromatography method, characterized in that the disturbing coextracts are separated on a silica column through which they are passed under pressure the mobile phase and the content of N- (1-formamido-2,2,2-trichloroethyl) morpholine are evaluated in the concentrated fraction of the mobile phase collected by the gas chromatography method.