Method for measuring residual quantity of thidiazuron and diuron as well as metabolites thereof in cotton

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 solventssuch 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

[0001] Technical field:

[0002] The invention belongs to the technical field of measuring pesticide residues in cotton, and relates to a method for measuring residues of thiadizuron, diuron and their metabolites in cotton. Background technique:

[0003] The growth and development of plants is affected by external environmental conditions, such as water, sunlight, cotton, temperature, etc., and controlled by internal genetic factors, while certain metabolic substances, phytohormones, regulate and control plant physiological activities. The discovery of plant hormones is a huge advance in the field of biology. It promotes the application of "chemical regulation" in agriculture, making it possible to change the inherent mode of plant growth and development through chemical regulation. The purpose of studying plant hormones is not only to reveal their mechanism of action in the process of regulating plant growth and development and the regularity of regulation and control, but m...

Examples

Embodiment 1

[0049] (1) Extraction: Weigh 20.0 g of cotton, place it in a stoppered Erlenmeyer flask, add 50 mL of acetonitrile, 10 mL of distilled water, shake and extract on a shaker for 60 min, add 6.0 g of sodium chloride to the filtrate, shake for 2 min, and let the layers stand still. Collect the upper organic phase, dehydrate it with anhydrous sodium sulfate, concentrate under reduced pressure in a water bath at 40°C to dryness, blow dry with nitrogen, add 10 mL of ethyl acetate, and wait for purification;

[0050] (2) Purification: use a C18 column, pre-spray with 5mL ethyl acetate, load the sample, rinse with 10mL ethyl acetate, collect the eluent, concentrate under reduced pressure in a 40°C water bath, blow dry with nitrogen, and constant volume with 2mL methanol , membrane filtration.

[0051] (3) Determination: Determination by DAD detector, mobile phase: methanol / water, 50 / 50 (V / V) flow rate: 0.5mL / min chromatographic column: XDB-C18, 1.8μm, 4.6×50mm, sample injection: 5 μL,...

Embodiment 2

[0053] (1) Extraction: Weigh 20.0 g of cotton and place it in a stoppered Erlenmeyer flask; add 80 mL of acetonitrile and 20 mL of distilled water, shake and extract on a shaker for 100 min, add 10 g of sodium chloride to the filtrate, shake for 5 min, statically separate layers, and collect The upper organic phase was dehydrated by anhydrous sodium sulfate, concentrated under reduced pressure in a water bath at 40°C to near-dryness, blown dry with nitrogen, and added 20 mL of ethyl acetate to be purified;

[0054] (2) Purification: use a C18 column, pre-spray with 5mL ethyl acetate, load the sample, rinse with 10mL ethyl acetate, collect the eluent, concentrate under reduced pressure in a 40°C water bath, blow dry with nitrogen, and constant volume with 2mL methanol , membrane filtration.

[0055] (3) Determination: Determination by DAD detector, mobile phase: methanol / water, 50 / 50 (V / V) flow rate: 0.5mL / min chromatographic column: XDB-C18, 1.8μm, 4.6×50mm, sample injection: ...

Embodiment 3

[0057] (1) Extraction: Weigh 20.0g of cotton, place it in a stoppered Erlenmeyer flask, add 50mL of acetonitrile, 10mL of distilled water, shake and extract on a shaker for 60min, add 8g of sodium chloride to the filtrate, shake for 4min, statically separate layers, collect The upper organic phase was dehydrated by anhydrous sodium sulfate, concentrated under reduced pressure in a water bath at 40°C to near-dryness, blown dry with nitrogen, and added 10 mL of ethyl acetate to be purified;

[0058] (2) Purification: use a C18 column, pre-spray with 5mL ethyl acetate, load the sample, rinse with 10mL ethyl acetate, collect the eluent, concentrate under reduced pressure in a 40°C water bath, blow dry with nitrogen, and constant volume with 2mL methanol , membrane filtration.

[0059] (3) Determination: Determination by DAD detector, mobile phase: methanol / water, 50 / 50 (V / V) flow rate: 0.5mL / min chromatographic column: XDB-C18, 1.8μm, 4.6×50mm, sample injection: 5 μL, column temp...

[0001] Technical field:

[0002] The invention belongs to the technical field of measuring pesticide residues in cotton, and relates to a method for measuring residues of thiadizuron, diuron and their metabolites in cotton. Background technique:

[0003] The growth and development of plants is affected by external environmental conditions, such as water, sunlight, cotton, temperature, etc., and controlled by internal genetic factors, while certain metabolic substances, phytohormones, regulate and control plant physiological activities. The discovery of plant hormones is a huge advance in the field of biology. It promotes the application of "chemical regulation" in agriculture, making it possible to change the inherent mode of plant growth and development through chemical regulation. The purpose of studying plant hormones is not only to reveal their mechanism of action in the process of regulating plant growth and development and the regularity of regulation and control, but m...

Examples

Embodiment 1

[0049] (1) Extraction: Weigh 20.0 g of cotton, place it in a stoppered Erlenmeyer flask, add 50 mL of acetonitrile, 10 mL of distilled water, shake and extract on a shaker for 60 min, add 6.0 g of sodium chloride to the filtrate, shake for 2 min, and let the layers stand still. Collect the upper organic phase, dehydrate it with anhydrous sodium sulfate, concentrate under reduced pressure in a water bath at 40°C to dryness, blow dry with nitrogen, add 10 mL of ethyl acetate, and wait for purification;

[0050] (2) Purification: use a C18 column, pre-spray with 5mL ethyl acetate, load the sample, rinse with 10mL ethyl acetate, collect the eluent, concentrate under reduced pressure in a 40°C water bath, blow dry with nitrogen, and constant volume with 2mL methanol , membrane filtration.

[0051] (3) Determination: Determination by DAD detector, mobile phase: methanol / water, 50 / 50 (V / V) flow rate: 0.5mL / min chromatographic column: XDB-C18, 1.8μm, 4.6×50mm, sample injection: 5 μL,...

Embodiment 2

[0053] (1) Extraction: Weigh 20.0 g of cotton and place it in a stoppered Erlenmeyer flask; add 80 mL of acetonitrile and 20 mL of distilled water, shake and extract on a shaker for 100 min, add 10 g of sodium chloride to the filtrate, shake for 5 min, statically separate layers, and collect The upper organic phase was dehydrated by anhydrous sodium sulfate, concentrated under reduced pressure in a water bath at 40°C to near-dryness, blown dry with nitrogen, and added 20 mL of ethyl acetate to be purified;

[0054] (2) Purification: use a C18 column, pre-spray with 5mL ethyl acetate, load the sample, rinse with 10mL ethyl acetate, collect the eluent, concentrate under reduced pressure in a 40°C water bath, blow dry with nitrogen, and constant volume with 2mL methanol , membrane filtration.

[0055] (3) Determination: Determination by DAD detector, mobile phase: methanol / water, 50 / 50 (V / V) flow rate: 0.5mL / min chromatographic column: XDB-C18, 1.8μm, 4.6×50mm, sample injection: ...

Embodiment 3

[0057] (1) Extraction: Weigh 20.0g of cotton, place it in a stoppered Erlenmeyer flask, add 50mL of acetonitrile, 10mL of distilled water, shake and extract on a shaker for 60min, add 8g of sodium chloride to the filtrate, shake for 4min, statically separate layers, collect The upper organic phase was dehydrated by anhydrous sodium sulfate, concentrated under reduced pressure in a water bath at 40°C to near-dryness, blown dry with nitrogen, and added 10 mL of ethyl acetate to be purified;

[0058] (2) Purification: use a C18 column, pre-spray with 5mL ethyl acetate, load the sample, rinse with 10mL ethyl acetate, collect the eluent, concentrate under reduced pressure in a 40°C water bath, blow dry with nitrogen, and constant volume with 2mL methanol , membrane filtration.

[0059] (3) Determination: Determination by DAD detector, mobile phase: methanol / water, 50 / 50 (V / V) flow rate: 0.5mL / min chromatographic column: XDB-C18, 1.8μm, 4.6×50mm, sample injection: 5 μL, column temp...

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