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Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email. GB 23200.4-2016: Food safety national standard -- Methods for the determination of herbicide residues -- Part 4: Determination of aryloxyphenoxypropionate herbicides in food by gas chromatography-mass spectrometry / mass spectrometry Status: Valid
Basic dataStandard ID: GB 23200.4-2016 (GB23200.4-2016)Description (Translated English): Food safety national standard -- Methods for the determination of herbicide residues -- Part 4: Determination of aryloxyphenoxypropionate herbicides in food by gas chromatography-mass spectrometry / mass spectrometry Sector / Industry: National Standard Classification of Chinese Standard: G25 Word Count Estimation: 15,142 Date of Issue: 2016-12-18 Date of Implementation: 2017-06-18 Older Standard (superseded by this standard): SN/T 1737.4-2010 Regulation (derived from): State Health Commission, Ministry of Agriculture, Food and Drug Administration Notice No. 16 of 2016 Issuing agency(ies): National Health and Family Planning Commission of the People's Republic of China, State Food and Drug Administration GB 23200.4-2016: Food safety national standard -- Methods for the determination of herbicide residues -- Part 4: Determination of aryloxyphenoxypropionate herbicides in food by gas chromatography-mass spectrometry / mass spectrometry---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order. Food safety national standard - Methods for the determination of herbicide residues - Part 4. Determination of aryloxyphenoxypropionate herbicides in food by gas chromatography - mass spectrometry/mass spectrometry National Standards of People's Republic of China GB Replace SN/T 1737.4-2010 National standards for food safety Method for determination of herbicide residue Part 4. Determination of food by gas chromatography - mass spectrometry/mass spectrometry The amount of aryloxyphenoxypropionate herbicide in the product National food safety standards- Determination of aryloxyphenoxypropionate herbicide residues in foods Gas chromatography - mass spectrometry 2016-12-18 Release.2017-06-18 Implementation National Health and Family Planning Commission of the People 's Republic of China Issued by the Ministry of Agriculture of the People 's Republic of China State Administration of Food and Drug Administration ForewordThis standard replaces SN/T 1737.4-2010 "Method for the determination of herbicide residues Part 4. Determination of access to and out of gas and mass spectrometry Oral products in the aryloxyphenoxypropionate ". Compared with SN/T 1737.4-2010, the main changes are as follows. - Standard text format is modified to national standard text format for food safety; - the name of the "import and export food" to "food"; - increase the "other food reference implementation" in the standard range. This standard replaced the previous version of the standard release. -SN/T 1737.4-2010. National standards for food safety Method for determination of herbicide residue Part 4. Determination of Aryloxyphenoxypropyl in Food by Gas Chromatography - Mass Spectrometry/Mass Spectrometry Acid herbicide residues1 ScopeThis standard stipulates that the food in the 2,4-dibutyl ester, fluphenazine, pheophorone, acetylclovir, grass grass, cyhalothrin, oxazole Determination of Aromatic Phenoxy Propionate Herbicide Residue by Gas Chromatography - Mass Spectrometry/Mass Spectrometry. This standard applies to soybeans, barley tea, japonica rice, carrots, spinach, green concanavalin, garlic, strawberry, honey, pork, fish, eggs In the 2,4-D butyl ester, fluphenazine, pherofen grass spirit, acetophene grass, grass grass, cyhalothrin, oxazole grass spirit, quinoxaline residues Of the determination and confirmation, other food can refer to the implementation.2 normative reference documentsThe following documents are indispensable for the application of this document. For dated references, only the dated edition applies to this article Pieces. For undated references, the latest edition (including all modifications) applies to this document. GB 2763 National Standard for Food Safety - Maximum Residue Limit of Pesticides in Foodstuffs GB/T 6682 Analytical laboratory water specifications and test methods3 principleThe residual aryloxyphenoxypropionate herbicide in the sample was extracted with n-hexane saturated acetonitrile (containing 1% glacial acetic acid), and the matrix was dispersed in solid phase Extraction and purification, with gas chromatography - mass spectrometry/mass spectrometry, external standard method quantitative.4 reagents and materialsUnless otherwise specified, all reagents are of analytical grade and water is in accordance with the primary water specified in GB/T 6682. 4.1 Reagents 4.1.1 Acetonitrile (CH3CN). Chromatographically pure 4.1.2 n-hexane (C6H14). pure chromatography. 4.1.3 Acetone (C3H6O). Chromatographic pure. 4.1.4 glacial acetic acid (C2H4O2). 4.1.5 anhydrous sodium acetate (C2H3ONa). 4.1.6 anhydrous magnesium sulfate (MgSO4). 4.2 solution preparation 4.2.1 Extraction solvent (1% acetic acid in n-hexane saturated acetonitrile solution). add 10 mL of glacial acetic acid to 990 mL of acetonitrile (prior Saturated with n-hexane). 4.3 standards 4.3.1 Aryloxyphenoxypropionate Herbicide Standard. 2,4-D butylate, CAS No. 94-80-4, Molecular formula. C12H14Cl2O3, purity & gt; 97.1%); fluorofenrofen (CAS. 69806-34-4, molecular formula. C15H11ClF3NO4, pure (Fluazifop, CAS No. 69335-91-7, molecular formula. C15H12F3NO4, purity ≥99%); alkyne (Clodinafop-propargyl, CAS number. 105512-06-9, molecular formula. C17H13ClFNO4, purity ≥99.0%); grass (Diclofop, CAS. 51338-27-3, molecular formula. C16H14Cl2O4, purity ≥ 96.5%); Cyhalofop-butyl CAS No.. 122008-85-9, Molecular formula. C20H20FNO4, purity ≥99.0%); oxazolium (Fenoxaprop, CAS. 95617-09-7, Molecular formula. C16H12ClNO5, purity ≥99%); Quizalofop-P-ethyl, CAS No.. 100646-51-3, molecular formula. C19H17ClN2O4, purity ≥99.5%). 4.4 standard solution preparation 4.4.1 Aryloxyphenoxypropionate Herbicide Standard stock solution. accurately weighed the standard amount of aryloxyphenoxypropionate herbicides, Acetone dissolved, diluted and constant volume, respectively, prepared into a 100 μg/mL single standard stock solution, the solution can be 0 ℃ ~ 4 ℃ under the conditions to avoid Light storage for 6 months. 4.4.2 Mixing standard intermediate solution. Accurate extraction of the standard stock solution for each aryloxyphenoxypropionate 5.0 mL in 50 mL of brown Flask, diluted with acetone to the mark line after the preparation of a concentration of 10.0 μg/mL mixed standard intermediate solution, the solution can be 0 ℃ ~ 4 ℃ Under the conditions of storage for 3 months. 4.4.3 mixed standard working solution. if necessary, then diluted with acetone to the appropriate concentration of mixed standard working solution, is now available. 4.5 Materials 4.5.1 Ethylenediamine-N-propylsilane (PSA) Filler. 40 μm to 60 μm. 4.5.2 Graphitized carbon black filler. 120 μm -400 μm. 4.5.3 Octadecylsilane (ODS) Filler. 60 μm to 100 μm. 4.5.4 Filtration. 0.45 μm, organic phase.5 instruments and equipment5.1 Gas Chromatography - Mass Spectrometry/Mass Spectrometry. 5.2 Oscillator. 5.3 Electronic balance. 0.01 g and 0.0001 g. 5.4 Scroll Mixer. 5.5 Tissue crusher. 5.6 pulverizer. 5.7 Rotary Evaporator. 5.8 Nitrogen Drying Machine. 5.9 stoppered conical flask. 250 mL. 5.10 test tube. 10 mL. 5.11 Concentrated Bottle. 150 mL.6 Preparation and storage of samples6.1 Preparation of the sample 6.1.1 carrot, green concanavalin, garlic, strawberry, spinach Take a representative sample of about 500 g (can not be washed with water), chopped, with the tissue crusher to sample into a slurry, into the clean Container, sealed and marked. 6.1.2 Soya, barley tea, japonica Take a representative sample of about 500 g (can not be washed with water), chopped, with the tissue crusher to sample into a slurry, into the clean Container, sealed and marked. 6.1.3 pork, fish, eggs Take a representative sample of about 500 g, chopped, with the tissue crusher will be fully mashed evenly, into a clean container, sealed and marked Remember. 6.1.4 honey Take a representative sample of about 500 g, the crystallization of honey samples will be evenly stirred; on the crystallization of honey samples, in the closed In the case of the vial placed in a water bath of not more than 60 ℃ in the warm, shaking, until the sample all melted and stir well, quickly cooled to room temperature, in the Melting should be taken to prevent moisture evaporation. Into a clean container, sealed and marked. Note. The above sample sampling site according to GB 2763 Appendix A implementation. 6.2 Sample storage Soybeans, barley tea, rice, honey and eggs and other samples stored below 4 ℃; carrots, green concanavalin, garlic, strawberry, spinach, Pork, fish, lobster and other samples stored below -18 ℃. During the operation of the sample preparation, the sample should be protected from contamination or changes in the content of the residue.7 Analysis steps7.1 Extraction 7.1.1 Carrot, green concanavalin, garlic, strawberry and spinach Weigh 10 g of sample (accurate to 0.01 g) in a 250 mL stoppered flask with 15 g of anhydrous magnesium sulfate, 6 g of anhydrous sodium acetate and 50 mL The solvent was extracted, shaken on an oscillator for 30 min, allowed to stand for 10 min, and filtered in a 150 mL concentration flask. The residue was then added to 20 mL of the extraction solvent Extract once, merge the filtrate twice, spin at 40 ° C to dry. Dissolve the residue with 2 mL of acetonitrile to be purified. 7.1.2 Soybeans, japonica rice, pork, fish and eggs Weigh 5 g of sample (accurate to 0.01 g) in 250 mL stoppered vials, add 15 g of anhydrous magnesium sulfate, 6 g of anhydrous sodium acetate and 50 mL Extraction of solvent, oscillation on the oscillator for 30 min (pork, fish, honey, eggs and other meat products should be homemade extraction 5 min), standing 10 min, Filtered in 150 mL concentrated bottles. Residue and then add 20 mL of extraction solvent extraction time, combined twice the filtrate, 40 ℃ rotation concentrated to dry. Dissolve the residue with 2 mL of acetonitrile to be purified. 7.1.3 barley tea Weigh 5 g of sample (accurate to 0.01 g) in 250 mL stoppered vials, add 5 mL of water to soak overnight, then add 15 g of anhydrous sulfuric acid Magnesium, 6 g of anhydrous sodium acetate and 50 mL of extraction solvent, shaken on an oscillator for 30 min, allowed to stand for 10 min, filtered in 150 mL concentrated bottles. Residue and then add 20 mL of extraction solvent extraction time, combined twice the filtrate, 40 ℃ rotation concentrated to dry. The residue was dissolved in 2 mL of acetonitrile, To be purified. 7.1.4 honey Weigh 5 g of sample (accurate to 0.01 g) in 250 mL stoppered vials, add 5 mL of water and add 15 g of anhydrous magnesium sulfate, 6 G of anhydrous sodium acetate and 50 mL of extraction solvent, shaken on an oscillator for 30 min, allowed to stand for 10 min, filtered in 150 mL concentrated bottles. Residue again Add 20 mL of extraction solvent extraction time, combined with two filtrates, 40 ° C rotation concentrated to dry. Dissolve the residue with 2 mL of acetonitrile to be purified. 7.2 Purification 7.2.1 carrot, green concanavalin, garlic, strawberry, spinach and barley tea extract The corresponding sample extract of 6.1 was transferred to a small tube containing.200 mg of PSA filler and 250 mg of graphitized carbon black filler in advance. Vortex 1 min, until the pigment is completely eliminated, the filter membrane, gas chromatography - mass spectrometry and confirmation. 7.2.2 Soybean, rice, pork, fish, honey and poultry extract The corresponding sample extract of 6.1 was transferred to a solution containing.200 mg of PSA filler, 150 mg of graphitized carbon black filler and 100 mg of C18 filler in advance Small test tube, full vortex 1 min, filter membrane, gas chromatography - mass spectrometry determination and confirmation. 7.3 Determination 7.3.1 Gas Chromatography - Mass Spectrometry Reference Conditions A) Column. DB-5ms Elastic quartz capillary column, 30 m × 0.25 mm (inner diameter) × 0.25 μm, or equivalent; B) Column temperature. initial temperature 50 ℃ (2min), 30 ℃/min to 180 ℃, then 5 ℃/min to 280 ℃ (for 10min); C) Inlet temperature. 250 ° C; D) chromatographic - mass spectrometer interface temperature. 280 ° C; E) Carrier gas. helium, purity greater than or equal to 99.999%; carrier gas flow rate. 1 mL/min; F) Injection volume. 1 μL; G) Injection method. splitless injection, 1.2 min after the opening valve; H) ion source. electron bombardment ion source (EI source); I) ion source temperature. 230 ° C; J) Electronic energy. 70 eV; K) solvent delay time. 9.0 min; L) scanning method. reactive ion monitoring mode (SRM); parent ion and daughter ion see Table 1. Table 1 Select ion and retention time Chinese name retention time (min) parent ion (m/z) ion ion (m/z) collision energy (V) 2,4-D butyl ester 12.07 175.9 111.0 15 277.1 185.0 * 5 185.6 155.0 15 Fluprofen 15.31 288.9 180.0 30 316.7 91.0 * 15 Phenanthrene 254.5 146.0 25 282.3 91.0 * 20 383.4 282.0 10 Acetyl Acetate 19.20 238.8 130.0 15 349.8 266.0 * 10 Herbs Ling 19.68 254.2 162.0 * 15 341.1 253.0 10 Cyhalofloxacin 22.49 256.3 120.0 * 10 357.4 256.0 10 Oxazolam herbin 23.74 288.8 91.0 20 119.0 10 361.8 288.0 * 10 Quizaline Wo Ling 26.23 299.8 91.0 20 372.9 299.0 * 10 7.3.2 Determination and confirmation of chromatography According to the content of the sample in the sample, select the concentration of similar standard working solution. Standard working solution and sample solution of aryloxyphenoxypropane The response values of the acid esters should be within the linear range of the instrument. The standard working solution and sample solution were measured by volume injection. If the sample solution is in the selective ion chromatogram of the standard working solution, a chromatographic peak appears at the same retention time, and after subtracting the background After the sample quality chromatogram, the selected ions are present, the abundance of the selected ions is higher than the abundance ratio of the corresponding ions of the standard. Within the allowable range (see Table 2). Under the above chromatographic conditions, the retention times of aryloxyphenoxypropionates are shown in Table 1, respectively. Aryloxyphenoxy The total ion chromatogram and full scan mass spectrum of gas chromatographic-mass spectrometry/mass spectrometry for propionate standards are shown in Figure A.1 and Appendix B of Appendix A B.1 Table 2 shows the maximum allowable error of relative ion abundance using gas chromatography-mass spectrometry 7.4 blank experiment In addition to the sample, according to the above determination steps.8 results are calculated and expressedCalculate the residual content of aryloxyphenoxypropionate in the sample by chromatographic data processor or formula (1). The calculated result is deducted from the blank value. MAs VCA (1) Where. Xi - Residue of aryloxyphenoxypropionate in the sample, in micrograms per kilogram (μg/kg); The peak area of aryloxyphenoxypropionate in sample solution; Ci - Concentration of aryloxyphenoxypropionate in standard working fluid, in ng/ml (ng/mL); V - the final volume of the sample solution in milliliters (mL); Asi - the peak area of aryloxyphenoxypropionate in standard working fluid; M - the mass of the sample represented by the final sample, in grams (g). Note. The result of the calculation must be deducted from the blank value. The result of the measurement is expressed as the arithmetic mean of the parallel measurement, and the two valid digits are retained.9 precision9.1 The ratio of the absolute difference between the two independent determinations obtained under reproducibility and its arithmetic mean (percentage) shall be in accordance with Appendix D requirements. 9.2 The ratio of the absolute difference between the two independent determinations obtained under reproducibility and its arithmetic mean (percentage) shall be in accordance with Appendix E requirements. 10% limit and recovery rate 10.1 Quantitation limits Relative abundance (base) 50% 20% to 50% 10% to 20% ≤10% Allowable relative deviation ± 20% ± 25% ± 30% ± 50% The quantification limit of this method is 0.005 mg/kg. 10.2 Recovery rate See Appendix C for the recovery range at the additional concentration levels in the different matrices.Appendix A(Informative) Figure A.1 Aromatic phenoxy propionate standard substance Total ion chromatogram Figure A.1 Aryloxyphenoxypropionate mixed standard solution Total ion chromatogram 1.2,4-dibutyl ester (12.093 min) 2. Fluprofen (15.349min) 3. Phenanthroline (17.363min) 4. Clenbuterol (19.197min) 5. Herbs (19.681min) 6. Cyhalothrin (22.485 min) 7. Oxazolam grass (23.739min) 8. Quinoxaline (26.227min)Appendix B(Informative) Aryloxyphenoxypropionate Standard Material Quality Chart Figure B.1 Aryloxyphenoxypropionate mixed standard solution Mass spectrumAppendix C(Informative) Concentration and Recovery Range of Aryloxyphenoxypropionate Pesticides in Different Substrates Table C.1 Concentration and Recovery Range of Aryloxyphenoxypropionate Pesticides in Different Substrates Sample name Pesticide name 0.005 mg/kg 0.010 mg/kg 0.020 mg/kg RSD (%) Soybeans 2,4-dibutyl ester 72.4 ~ 97.0 83.9 ~ 104.7 79.0 ~ 98.7 4.9 ~ 10.3 Fluprofen 79.8 ~ 106.6 76.3 ~ 93.6 81.9 ~ 97.6 5.5 ~ 10.6 Phenanthroline 75.2 ~ 101.1 79.4 ~ 100.6 77.4 ~ 93.1 7.3 ~ 10.3 Clenbuterol 71.0 ~ 99.8 71.9 ~ 91.2 79.0 ~ 94.9 5.6 ~ 10.4 Grasses 88.6 ~ 114.4 72.9 ~ 102.8 79.8 ~ 94.1 5.0 ~ 10.2 Cyhalofloxacin 75.4 ~ 106.0 72.9 ~ 101.9 78.9 ~ 94.3 4.9 ~ 10.3 Oxazole grass spirit 85.0 ~ 115.6 70.9 ~ 91.9 77.7 ~ 92.6 7.0 ~ 10.3 Jingqiu Wo Ling 77.2 ~ 107.8 75.0 ~ 101.6 78.8 ~ 92.6 5.7 ~ 10.7 Barley tea 2,4-D butyl ester 70.8 to 99.4 93.3 to 116.0 81.0 to 96.8 5.3 to 10.6 Fluoroproline 68.4 ~ 98.4 79.2 ~ 103.5 79.1 ~ 94.4 5.9 ~ 10.1 Pheophorone Cypriot 76.0 ~ 107.8 79.0 ~ 101.4 78.6 ~ 94.4 7.0 ~ 10.8 Clodine 86.6 ~ 99.0 78.5 ~ 91.5 82.8 ~ 91.2 5.1 ~ 10.9 Wo grass Ling 76.4 ~ 106.0 70.9 ~ 94.4 81.5 ~ 96.9 5.0 ~ 10.7 Cyhalofloxacin 78.2 ~ 113.0 72.7 ~ 94.3 79.8 ~ 9414 5.9 ~ 10.6 Oxazole grass spirit 79.4 ~ 110.4 74.5 ~ 98.6 78.8 ~ 9424 6.0 ~ 10.5 Jingqihao Ling 83.2 ~ 119.2 72.6 ~ 94.6 77.7 ~ 92.6 5.0 ~ 10.4 Rice 2,4-dibutyl ester 78.2 to 110.2 80.3 to 106.7 81.7 to 97.9 4.3 to 10.5 Fluoroproline 82.8 ~ 114.2 86.2 ~ 107.8 81.9 ~ 98.0 6.6 ~ 10.7 Phenanthroline Ling 90.8 ~ 118.8 78.9 ~ 101.7 83.8 ~ 98.9 4.8 ~ 10.1 Clenbuterol 76.0 ~ 101.4 75.9 ~ 105.7 82.8 ~ 98.3 5.2 ~ 10.4 Grasses 79.8 to 110.6 76.4 to 104.7 83.0 to 99.1 5.7 to 10.5 Cyhalofloxacin 74.4 ~ 99.4 84.9 ~ 111.7 81.9 ~ 97.6 6.3 ~ 8.5 Oxazolam grass spirit 78.8 ~ 111.2 80.1 ~ 110.1 81.9 ~ 97.6 4.1 ~ 10.7 Quirgine Wo Ling 77.4 ~ 103.8 78.6 ~ 106.7 79.0 ~ 95.2 5.7 ~ 9.7 carrot 2,4,6-butyl acetate 74.6 ~ 103.8 73.0 ~ 97.3 78.6 ~ 94.4 4.0 ~ 9.9 Fluprofen 88.6 ~ 114.8 70.9 ~ 94.4 81.1 ~ 96.0 5.7 ~ 10.5 Phenanthrene grass spirit 79.0 ~ 112.8 78.9 ~ 101.7 81.0 ~ 96.8 4.7 ~ 10.5 Clenbuterol 79.4 ~ 100.8 75.9 ~ 105.7 79.8 ~ 94.1 5.7 ~ 10.2 Wo grass spirit 81.6 ~ 116.2 76.4 ~ 104.7 80.3 ~ 96.4 5.9 ~ 10.7 Cyhalofloxacin 72.6 ~ 102.0 78.4 ~ 96.2 79.0 ~ 95.2 4.8 ~ 10.0 Oxadiazole grass spirit 70.8 ~ 96.6 75.4 ~ 98.4 80.6 ~ 95.8 4.3 ~ 10.7 Quizaline Ling 84.4 ~ 101.4 78.6 ~ 100.7 81.1 ~ 96.0 4.5 ~ 10.7 spinach 2,4-D butyl ester 75.4 to 98.0 81.2 to 105.6 79.1 to 98.8 4.6 to 10.3 Fluorophenanthrene 77.6 ~ 105.3 74.7 ~ 98.2 77.9 ~ 96.5 5.7 ~ 10.6 Phenanthroline grass 73.1 ~ 99.4 80.4 ~ 101.5 79.9 ~ 94.5 5.1 ~ 10.3 Clenbuterol 78.0 ~ 98.9 77.6 ~ 90.8 80.0 ~ 97.8 5.3 ~ 10.4 Wo grass Ling 82.4 ~ 104.5 77.6 ~ 106.3 78.9 ~ 95.6 5.2 ~ 10.2 Cyhalofloxacin 78.5 ~ 101.2 78.2 ~ 100.2 77.6 ~ 99.6 5.0 ~ 10.3 Oxazole grass spirit 84.3 ~ 101.9 71.4 ~ 95.6 78.2 ~ 94.7 5.9 ~ 10.3 Quinoline Wo Ling 78.3 ~ 99.8 77.6 ~ 104.2 88.1 ~ 95.7 4.1 ~ 10.7 Green concanavalin 2,4,4-drop butyl ester 79.4 ~ 103.8 69.3 ~ 90.3 79.8 ~ 94.9 3.0 ~ 10.3 Fluprofen 76.0 ~ 101.4 76.4 ~ 104.7 79.0 ~ 94.2 3.9 ~ 10.6 Phenanthroline grasses 79.8 ~ 110.6 78.9 ~ 101.7 82.8 ~ 98.0 5.2 ~ 10.2 Acetyl Acetate 74.4 ~ 103.2 74.6 ~ 99.1 79.0 ~ 94.4 4.0 ~ 10.4 Grasses 81.6 to 107.8 76.0 to 99.3 79.0 to 95.2 3.8 to 10.2 Cyhalofloxacin 77.2 ~ 103.4 77.3 ~ 98.5 82.0 ~ 98.0 6.3 ~ 10.3 Oxazole grass grass spi......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB 23200.4-2016_English be delivered?Answer: Upon your order, we will start to translate GB 23200.4-2016_English as soon as possible, and keep you informed of the progress. 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