CN101943685A - Method for measuring residual quantity of thidiazuron and diuron as well as metabolites thereof in cotton - Google Patents

Abstract

The invention relates to a method for measuring residual quantity of thidiazuron and diuron as well as metabolites thereof in cotton, which comprises the following concrete steps: weighing 20.0g of sample; putting the sample into a conical flask with a plug; adding 50mL of acetonitrile and 10mL of distilled water; oscillating and extracting for 60min on an oscillator; adding 6.0-10g of sodium chloride into the filtered solution; oscillating for 2-5min; standing for layering; collecting the organic phase at the upper layer; dehydrating by anhydrous sodium sulfate; carrying out decompression concentration in a water bath at 40 DEG C for nearly drying; blow-drying by nitrogen gas; adding 10-20mL of ethyl acetate; then pre-leaching by adopting a C18 column and 5mL of ethyl acetate; sampling; leaching by 10mL of ethyl acetate; collecting the leacheate; carrying out decompression concentration in the water bath at 40 DEG C for nearly drying; blow-drying by nitrogen gas; metering the volume by 2mL of methanol; filtering by a filter membrane; and measuring by adopting a DAD detector. The measuring method of the invention simplifies the extracting steps, reduces the consumption of solvents such as toluene dichloride and the like, and reduces the interference of impurities in the sample by using solid phase extraction and purification so that the result is more accurate, sensitive and reliable.

Description

The determination of residual amount method of Thidiazuron and diuron and metabolin thereof in the cotton

The art field:

The invention belongs to the determination techniques field of persticide residue in the cotton, relate to the determination of residual amount method of Thidiazuron and diuron and metabolin thereof in the cotton.

Background technology:

The growth and development of plant process is subjected to external environmental condition, and as the influence of moisture, sunlight, cotton, temperature etc. and the control of inner inherent cause, and what regulate the activity of control plant physiology is some metabolite, i.e. plant hormone.The discovery of plant hormone is the huge advance made in the field of biology.It has promoted " chemical regulation " application in agricultural, makes people might change the natural mode of plant growth, growth by chemical regulation.The purpose of research plant hormone, be not only in order to disclose its mechanism of action in the coordinate plant growth growth course and the regularity of regulating control, the more important thing is the application technology of exploring plant growth substance, make it by producing needs, the regulation and control growth and development of plant improves quality and the output of crop.Present chemical regulation technique, farming, woods, herd, widespread use in the field such as gardening, flowers, breeding, cultivation management, raising plant resistance to environment stress, and obtained certain effect, be subjected to biological, chemical science and technology worker and cultivation, breeding work person's attention.In some cases, reasonably the production effect of appliable plant growth substance even ratio cultivation are faster with breeding.

Thidiazuron (thidiazuron) chemical name 1-phenyl-3-(1,2,3-thiadiazoles-5-yl) urea is a plant growth regulators, does defoliant and use on cotton planting.Diuron (Diuron) chemical name N-3,4-dichlorophenyl-N ', N '-dimethyl urea is the inner sucting conduction type broad-spectrum herbicide, belongs to the internal-suction type herbicide, can suppress the crop photosynthesis effect, is used to prevent and kill off the general weeds in noncrop area.Be mainly used in cotton, corn, jowar, sugarcane, paddy rice, tea place, orchard, vineyard and bare place.Its assay method has liquid phase process, gas phase process etc.Application number: 200710022396 disclose a kind of method of removing herbicide Dailon in the water, and it is to adopt medium blocking-discharge method that the water that contains herbicide Dailon is handled, and the diuron in the water body is degraded; With contaminant degradation is carbon dioxide, water and simple organic, the reaction conditions gentleness, and controllability is stronger, reactor apparatus and operate fairly simple.Other are about enemy's Thidiazuron and diuron and metabolin (DCPU, the residue detection analysis of residual quantity DCPMU) in cotton, the present domestic open report of not seeing.

Summary of the invention:

The present invention adopts liquid phase chromatography by the Thidiazuron in the cotton and diuron and the research of the metabolin interpolation recovery thereof, sets up grand and diuron and metabolite residue analytical approach thereof of benzene in the simple and direct feasible cotton.Specifically be to use organic solvent that Thidiazuron in the cotton and metabolin, diuron and metabolin thereof are extracted, in extract, add sodium chloride then, isolate organic solvent layer by liquid liquid, and utilize rotary evaporation to be concentrated into isolated organic solvent layer dried fully, utilize solid phase extraction to remove interfering material in the extract, adopt liquid phase chromatography to carry out the research of detection method at last.For achieving the above object, the invention provides following technical scheme:

The determination of residual amount method of Thidiazuron and diuron and metabolin thereof in the cotton, undertaken by following step:

(1) extracts: take by weighing sample 20.0g, place tool plug conical flask, add the 50-80mL acetonitrile, 10-20mL distilled water, 60-100min is extracted in vibration on oscillator, and filtrate places the 500mL separating funnel, add 6.0-10g sodium chloride, vibration 2-5min, static layering, collect upper organic phase, through anhydrous sodium sulfate dehydration, concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, add 10-20mL ethyl acetate, to be clean;

(2) purify: adopt the C18 post, the pre-leaching of 5mL ethyl acetate, last sample, leacheate is collected in the drip washing of 10mL ethyl acetate, and concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, methyl alcohol 2mL constant volume, membrane filtration.

(3) measure: adopt the DAD detecting device to measure, wherein moving phase: methanol, 50/50 (V/V) flow velocity: 0.5mL/min chromatographic column: XDB-C18,1.8 μ m, 4.6 * 50mm, sample introduction: 5 μ L, column temperature: 40 ℃ of wavelength: 0-4min 290nm, 254nm behind the 4min.

Diuron of the present invention and metabolin thereof are: and diuron (diuron) 3-(3,4-dichlorophenyl)-1,1-dimethylurea and can be converted into 3, the metabolin of 4-dichloroaniline.

Thidiazuron of the present invention (thidiazuron) and metabolin thereof are Thidiazuron and the aniline that contains metabolin thereof.

The concrete assay method of the residual quantity of Thidiazuron and diuron and metabolin thereof is as follows in the cotton:

One, reagent and instrument

Agilent 1200 liquid chromatographs, BUCHI rotary evaporator, HZQ-C air bath oscillator, IKA refiner acetonitrile (analyze pure, heavily steam), ethyl acetate (analyzes pure, heavily steaming), anhydrous sodium sulfate, sodium chloride (analyzing pure), methyl alcohol (chromatographically pure)

Standard specimen: Thidiazuron (98.3%), Thidiazuron metabolin thidiazolylurea (90.0%), diuron (99.6%), diuron metabolin DCPU (99.5%), DCPMU (99.0%)

The blended standard reserving solution: accurately taking by weighing above standard sample of pesticide respectively, is solvent with methyl alcohol, is mixed with mass concentration and is 20mgL ^-1The hybrid standard storing solution, in refrigerator, preserve.

Two, the preparation of sample

1, pre-treatment process

Extract: take by weighing sample 20.0g, place tool plug conical flask, add the 50mL acetonitrile, 10mL distilled water, 60min is extracted in vibration on oscillator, and filtrate places the 500mL separating funnel, add the sodium chloride about 6.0g, vibration 2min, static layering, collect upper organic phase, through anhydrous sodium sulfate dehydration, concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, add 10mL ethyl acetate, to be clean.

Purify: the C18 post, the pre-leaching of 5mL ethyl acetate, last sample, leacheate is collected in the drip washing of 10mL ethyl acetate, and concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, methyl alcohol 2mL constant volume, membrane filtration.

2, instrument condition

Agilent 1200, the DAD detecting device

Moving phase: methanol, 50/50 (V/V)

Flow velocity: 0.5mL/min

Chromatographic column: XDB-C18,1.8 μ m, 4.6 * 50mm

Sample introduction: 5 μ L

Column temperature: 40 ℃

Wavelength: 0-4min 290nm, 254nm behind the 4min.

3, retention time

The Thidiazuron metabolin, 1.048min, Thidiazuron thidiazolylurea, 3.625min

Diuron metabolin DCPU, 5.214min. diuron metabolin DCPMU, 6.879min, diuron, 7.621min

4, instrument precision test

With the mixing standard specimen of agricultural chemicals, by above-mentioned instrument condition continuous sample introduction 5 pins, record the relative standard deviation of Thidiazuron and metabolin thidiazolylurea thereof and diuron and metabolin DCPU, DCPMU, see Table 1

Table 1. relative standard deviation

Agricultural chemicals	RSD(％)
		Thidiazuron	1.62
thidiazolylurea	2.83
		Diuron	1.31
DCPU	0.52
		DCPMU	1.91

5, recovery of standard addition and relative standard deviation

Add the hybrid standard product in blank cotton, the recovery and relative standard deviation see Table 2, table 3.The result meets the requirements, and has proved that this method has the recovery and repeatability preferably.

Table 2 Thidiazuron and metabolic product thereof add the recovery

Table 3 diuron and metabolic product thereof add recovery test

The assay method of Thidiazuron and diuron residual quantity and existing method compare in the cotton of the present invention, and the good effect that is had is:

(1) method of the present invention has been simplified extraction step, has reduced the use amount of dichlorotoleune equal solvent, purifies by using Solid-Phase Extraction, has reduced the interference of impurity in the sample, makes the result more accurate, sensitive, reliable.

(2) assay method of the present invention have simple and quick, recovery height, highly sensitive, impurity disturbs little characteristics.

Description of drawings:

Fig. 1 is for mixing the standard specimen chromatogram;

Fig. 2 is for adding chromatogram.

Embodiment:

In order to explain enforcement of the present invention more fully, provide the preparation embodiment of the determination of residual amount method of Thidiazuron and diuron and metabolin thereof in the cotton.These embodiments only are to explain rather than limit the scope of the invention.Wherein used raw material all has commercially available.

Embodiment 1

(1) extracts: take by weighing cotton 20.0g, place tool plug conical flask, add the 50mL acetonitrile, 10mL distilled water, 60min is extracted in vibration on oscillator, and filtrate adds 6.0g sodium chloride, vibration 2min, static layering is collected upper organic phase, through anhydrous sodium sulfate dehydration, concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, nitrogen dries up, and adds 10mL ethyl acetate, and is to be clean;

(2) purify: adopt the C18 post, the pre-leaching of 5mL ethyl acetate, last sample, leacheate is collected in the drip washing of 10mL ethyl acetate, and concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, methyl alcohol 2mL constant volume, membrane filtration.

(3) measure: adopt the DAD detecting device to measure, wherein moving phase: methanol, 50/50 (V/V) flow velocity: 0.5mL/min chromatographic column: XDB-C18,1.8 μ m, 4.6 * 50mm, sample introduction: 5 μ L, column temperature: 40 ℃ of wavelength: 0-4min 290nm, 254nm behind the 4min.

Embodiment 2

(1) extracts: take by weighing cotton 20.0g, place tool plug conical flask; Add the 80mL acetonitrile, 20mL distilled water, 100min is extracted in vibration on oscillator, and filtrate adds 10g sodium chloride, vibration 5min, static layering is collected upper organic phase, through anhydrous sodium sulfate dehydration, concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, and adds 20mL ethyl acetate, and is to be clean;

(2) purify: adopt the C18 post, the pre-leaching of 5mL ethyl acetate, last sample, leacheate is collected in the drip washing of 10mL ethyl acetate, and concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, methyl alcohol 2mL constant volume, membrane filtration.

(3) measure: adopt the DAD detecting device to measure, wherein moving phase: methanol, 50/50 (V/V) flow velocity: 0.5mL/min chromatographic column: XDB-C18,1.8 μ m, 4.6 * 50mm, sample introduction: 5 μ L, column temperature: 40 ℃ of wavelength: 0-4min 290nm, 254nm behind the 4min.

Embodiment 3

(1) extracts: take by weighing cotton 20.0g, place tool plug conical flask, add the 50mL acetonitrile, 10mL distilled water, 60min is extracted in vibration on oscillator, and filtrate adds 8g sodium chloride, vibration 4min, static layering is collected upper organic phase, through anhydrous sodium sulfate dehydration, concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, nitrogen dries up, and adds 10mL ethyl acetate, and is to be clean;

(2) purify: adopt the C18 post, the pre-leaching of 5mL ethyl acetate, last sample, leacheate is collected in the drip washing of 10mL ethyl acetate, and concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, methyl alcohol 2mL constant volume, membrane filtration.

(3) measure: adopt the DAD detecting device to measure, wherein moving phase: methanol, 50/50 (V/V) flow velocity: 0.5mL/min chromatographic column: XDB-C18,1.8 μ m, 4.6 * 50mm, sample introduction: 5 μ L, column temperature: 40 ℃ of wavelength: 0-4min 290nm, 254nm behind the 4min.

Retention time: Thidiazuron metabolin, 1.048min, Thidiazuron thidiazolylurea, 3.625min, diuron metabolin DCPU, 5.214min, diuron metabolin DCPMU, 6.879min, diuron, 7.621min.

After the preferred embodiment that describes in detail, being familiar with this technology personage can be well understood to, can carry out various variations and modification not breaking away under above-mentioned claim and the spirit, all foundations technical spirit of the present invention is done any simple modification, equivalent variations and modification to above embodiment, all belongs to the scope of technical solution of the present invention.And the present invention also is not subjected to the restriction of the embodiment that gives an actual example in the instructions.

Claims (2)

1. the determination of residual amount method of Thidiazuron and diuron and metabolin thereof in the cotton is characterized in that being undertaken by following step:

(1) extracts: take by weighing sample 20.0g, place tool plug conical flask, add the 50-80mL acetonitrile, 10-20mL distilled water, 60-100min is extracted in vibration on oscillator, and filtrate adds 6.0-10g sodium chloride, vibration 2-5min, static layering is collected upper organic phase, through anhydrous sodium sulfate dehydration, concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, nitrogen dries up, and adds 10-20mL ethyl acetate, and is to be clean;

(2) purify: adopt the C18 post, the pre-leaching of 5mL ethyl acetate, last sample, leacheate is collected in the drip washing of 10mL ethyl acetate, and concentrating under reduced pressure is closely dried under 40 ℃ of water-baths, and nitrogen dries up, methyl alcohol 2mL constant volume, membrane filtration.

(3) measure: adopt the DAD detecting device to measure, wherein moving phase: methanol, 50/50 (V/V) flow velocity: 0.5mL/min chromatographic column: XDB-C18,1.8 μ m, 4.6 * 50mm, sample introduction: 5 μ L, column temperature: 40 ℃ of wavelength: 0-4min 290nm, 254nm behind the 4min.

2. the described determination of residual amount method of claim 1, wherein the Thidiazuron metabolin is thidiazolylurea, the diuron metabolin is DCPU, DCPMU.

Images