Detection method for pesticide residues in tea leaves

A detection method, Zhongnong's technology, applied in the field of analysis and detection, can solve the problems of damage to the health of quality inspection personnel, increase the chance of toxic and harmful substances, and long working hours, and achieve accurate and reliable measurement results, easy operation, and high sensitivity. Effect

Active Publication Date: 2017-03-15
广西岑溪天晟茶业股份有限公司
View PDF2 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The main disadvantages of the existing detection methods are: (1) When detecting multiple pesticide residues, multiple methods need to be selected: that is, one method is only suitable for detecting a certain pesticide, and the work intensity is high, the working time is long, and the efficiency is low; (2) The operation is cumbersome, the efficiency is low, and the chances of inspectors coming into contact with toxic and harmful substances increase, which will damage the health of quality inspectors

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] In the embodiment of the present invention, a method for detecting pesticide residues in tea, comprising the following steps:

[0021] (1) Pre-treatment method: Weigh 1.0 g of the test sample, pulverize it, pass it through a 150-mesh sieve, add 3 mL of 0.05 mol / L hydrochloric acid solution, ultrasonically treat it for 20 min, filter, and then wash the residue with 15 mL of 0.05 mol / L hydrochloric acid solution 4 times. , the solution was adjusted to pH 8.5 with 0.2 mol / L sodium hydroxide solution, 1 mg of anhydrous sodium acetate, 0.5 mg of anhydrous magnesium sulfate and 3 mL of acetonitrile acetate were added, and reacted in a water bath at 60 °C for 1.5 h. Methyl chloride extraction, layering, the extraction was repeated twice, the combined extract was dried over anhydrous sodium sulfate, spin-dried, and made up to 1.0 mL with methanol, to be tested;

[0022] (2) The pretreated samples were quantitatively analyzed by GC-MS to obtain the content of pesticide residues ...

Embodiment 2

[0028] In the embodiment of the present invention, a method for detecting pesticide residues in tea, comprising the following steps:

[0029] (1) Pretreatment method: Weigh 1.0g of the test sample, pulverize it, pass it through a 300-mesh sieve, add 8mL of 0.8mol / L hydrochloric acid solution, ultrasonically treat it for 40min, filter, and then wash the residue with 30mL of 0.8mol / L hydrochloric acid solution 4 times. , the solution was adjusted to pH 9.0 with 0.8 mol / L sodium hydroxide solution, 4 mg of anhydrous sodium acetate, 6 mg of anhydrous magnesium sulfate and 40 mL of acetonitrile acetate were added, reacted in a water bath at 80 °C for 4 h, taken out and cooled, and 50 mL of chloroform was added. Extraction, layering, extraction repeated twice, the combined extracts were dried over anhydrous sodium sulfate, spin-dried, and made up to 1.0 mL with methanol, to be tested;

[0030] (2) The pretreated samples were quantitatively analyzed by GC-MS to obtain the content of ...

Embodiment 3

[0035] In the embodiment of the present invention, a method for detecting pesticide residues in tea, comprising the following steps:

[0036] (1) Pretreatment method: Weigh 1.0g of the test sample, pulverize it, pass it through a 200-mesh sieve, add 4 mL of 0.1 mol / L hydrochloric acid solution, ultrasonically treat it for 25 min, filter, and then wash the residue with 20 mL of 0.1 mol / L hydrochloric acid solution in 4 times. , the solution was adjusted to pH 8.5 with 0.3 mol / L sodium hydroxide solution, 1.5 mg of anhydrous sodium acetate, 1 mg of anhydrous magnesium sulfate and 5 mL of acetonitrile acetate were added, reacted in a water bath at 65 °C for 2 h, taken out and cooled, and 35 mL of trichloride was added. Methane extraction, layering, the extraction was repeated twice, the combined extracts were dried over anhydrous sodium sulfate, spin-dried, and made up to 1.0 mL with methanol, to be tested;

[0037] (2) The pretreated samples were quantitatively analyzed by GC-MS...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
diameteraaaaaaaaaa
thicknessaaaaaaaaaa
diameteraaaaaaaaaa
Login to view more

Abstract

The invention discloses a detection method for pesticide residues in tea leaves. The detection method includes the steps: weighing 1.0g of test samples, crushing and sieving the test samples, adding 0.05-0.8mol/L of hydrochloric acid solution, ultrasonically treating and filtering the test samples, washing residues by the aid of 0.05-0.8mol/L of hydrochloric acid solution, adjusting pH (potential of hydrogen) of the solution to be 8.5-9.0 by the aid of 0.2-0.8mol/L of sodium hydroxide solution, adding 1-4mg of anhydrous sodium acetate, 0.5-6mg of anhydrous magnesium sulfate and 3-40mL of acetic acid acetonitrile, performing reaction in water bath, taking out and cooling reaction products, adding trichloromethane, performing extraction and layering, repeating extraction twice, combining extraction liquid, drying the extraction liquid by the aid of anhydrous sodium sulfate, spin-drying the products, metering volume to 1.0mL by the aid of methyl alcohol, and waiting for testing; quantitatively analyzing pretreated samples by the aid of a GC-MS (gas chromatography-mass spectrometer) to obtain the content of the pesticide residues in the tea leaves. The detection method is high in sensitivity and stability, simple and convenient to operate, good in linear range and accurate and reliable in measuring result, has high accuracy and repeatability and can meet requirements for detecting the pesticide residues in the tea leaves, and sample adding recovery rate meets requirements.

Description

technical field [0001] The invention relates to the technical field of analysis and detection, in particular to a method for detecting pesticide residues in tea leaves. Background technique [0002] Tea has a long history in China. Tea has a protective effect on brain cells. Tea can effectively delay brain degeneration and help maintain the health of brain blood vessels. Tea can also eliminate fatigue, refresh, improve eyesight, digestion, diuresis and detoxification, prevent dental caries, and eliminate bad breath. Tea is also an alkaline beverage, which is conducive to the correction of acidic constitution. Tea safety issues are directly related to people's life and health. In order to reduce pesticide residues in tea and improve the competitiveness of my country's tea products, pesticide residue detection and analysis is a very important part. The shortcomings of the existing detection methods mainly include: (1) Multiple methods need to be selected when detecting a vari...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N30/02G01N30/06
CPCG01N30/02G01N30/06
Inventor 张根义胡彬张进吴念绮周朱晨
Owner 广西岑溪天晟茶业股份有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap