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GB 23200.110-2018: National food safety standard -- Determination of forchlorfenuron residues in plant-derived foods -- Liquid chromatography-mass spectrometry
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National food safety standard -- Determination of forchlorfenuron residues in plant-derived foods -- Liquid chromatography-mass spectrometry
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GB 23200.110-2018
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Basic data | Standard ID | GB 23200.110-2018 (GB23200.110-2018) | | Description (Translated English) | National food safety standard -- Determination of forchlorfenuron residues in plant-derived foods -- Liquid chromatography-mass spectrometry | | Sector / Industry | National Standard | | Classification of Chinese Standard | G25 | | Word Count Estimation | 7,724 | | Date of Issue | 2018-06-21 | | Date of Implementation | 2018-12-21 | | Regulation (derived from) | National Health and Wellness Commission Announcement No.6 of 2018 | | Issuing agency(ies) | National Health Commission of the People's Republic of China, State Administration for Market Regulation | GB 23200.110-2018: National food safety standard -- Determination of forchlorfenuron residues in plant-derived foods -- Liquid chromatography-mass spectrometry
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National Standards of People's Republic of China
National food safety standards
Determination of chlorfenuron residues in plant-derived foods
Liquid chromatography-mass spectrometry
State Administration for Market Regulation
Ministry of Agriculture and Rural Affairs of the People's Republic of China
National Health Commission of the People's Republic of China
National food safety standards
1 Scope
This standard specifies the liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS) method for the determination of clofenuron residues in plant-derived foods:
This standard is applicable to the determination of clofenuron residues in plant-derived foods:
2 Normative reference documents
The following documents are essential for the application of this document: For dated references, only the dated version applies to this document:
For undated referenced documents, the latest version (including all amendments) applies to this document:
GB 2763 National Food Safety Standard Maximum Residue Limits of Pesticides in Foods
GB/T 6682 Analytical laboratory water specifications and test methods
3 principles
The chlorfenuron in the sample was extracted with acetonitrile, purified by dispersive solid phase extraction, measured by liquid chromatography-mass spectrometry, and quantified by the external standard method:
4 Reagents and materials
Unless otherwise stated, only reagents confirmed to be of analytical grade and in compliance with
Class 1 water specified in GB/T 6682:
4:1 Reagents
4:1:1 Formic acid (HCOOH, CAS number: 64-18-6): chromatographically pure:
4:1:2 Acetonitrile (CH₃CN, CAS number: 75-05-8): chromatographically pure:
4:1:3 Anhydrous magnesium sulfate (MgSO∠, CAS number: 7487-88-9):
4:1:4 Sodium chloride (NaCl, CAS number: 12125-02-9):
4:2 Solution preparation
Formic acid solution (1 499, volume ratio): accurately absorb 1mL of formic acid and add 499mL of water, mix well, and then place it in ultrasonic for 15 minutes and set aside:
4:3 Standard products
Chlofenuron standard (C₁₂H₁₀CIN₃O, CAS number: 68157-60-8): purity ≥99:0%:
4:4 Preparation of standard solution
4:4:1 Chlorfenuron standard stock solution (100mg/L): Accurately weigh 10mg (accurate to 0:1mg) of Chlorfenuron standard in a 50mL beaker, dissolve it in acetonitrile and transfer it to a 100mL volumetric flask, and dilute to volume with acetonitrile: Fill to the mark, mix well, and store in a freezer at -18°C away from light: The validity period is 6 months:
4:4:2 Chlorfenuron standard working solution (10 mg/L): Accurately draw 1 mL of standard stock solution, add it to a 10 mL volumetric flask, dilute to volume with acetonitrile, and mix: Stored at 4℃, the validity period is 1 month:
4:5 Materials
4:5:1 N-propylethylenediamine (PSA), 40pm~60pm:
4:5:2 Graphitized carbon black (GCB), 38pm~120pm:
4:5:3 Octadecyl bonded silica gel (Cis), 50μm:
4:5:4 Filter membrane: 0:22μm, organic system:
5 Instruments and equipment
5:1 Liquid chromatography-mass spectrometer: equipped with electrospray ion source (ESI):
5:2 Analytical balance, sensitive to 0:01g and 0:0001g:
5:3 Centrifuge, the rotation speed is not less than 8000 r/min:
5:4 Vortex oscillator:
6 Preparation of specimens
Samples of vegetables, fruits and edible fungi should be taken in certain quantities in accordance with relevant standards, and the sampling locations should be in accordance with the provisions of GB 2763: For small individual samples, all are processed after sampling; for large individual and basically uniform samples, they can be divided or cut into small pieces on the axis or plane of symmetry and then processed; for slender, flat or component content in each part For samples with differences, small pieces or segments can be cut from different parts for processing; the sample should be chopped into small pieces, mixed thoroughly, and sampled using the quartering method or directly put into a tissue masher and mashed into a homogenate: : The homogenate was placed in a polyethylene container:
Take 500g of cereal samples, crush them so that they can all pass through a 425μm standard mesh sieve, and put them into polyethylene bottles or bags: Take 500g each of oil crops, tea leaves, nuts and spices samples, crush them and mix thoroughly, then put them into polyethylene bottles or bags:
Mix the vegetable oil evenly: Samples are stored at -18°C and below:
7 Analysis steps
7:1 Extraction
7:1:1 Vegetables, fruits, edible fungi, vegetable oils
Weigh 10g (accurate to 0:01g) sample into a 50mL centrifuge tube, add 10mL acetonitrile, vortex and extract for 3 minutes; add 4g anhydrous magnesium sulfate and 1g sodium chloride to the centrifuge tube for vegetables, fruits, and edible fungi: , vegetable oil, add 5g sodium chloride to the centrifuge tube, vortex for 1 min; then centrifuge at 4000 r/min for 5 min, and take 1:5 mL of supernatant for purification:
7:1:2 Cereals, oilseeds, nuts
Weigh 5g (accurate to 0:01g) of the sample into a 50mL centrifuge tube, add 10mL of water, and vortex for 30 seconds to completely wet the sample; then add 10mL of acetonitrile, vortex and extract for 3 minutes; add 5g of chlorine to the centrifuge tube: sodium, vortex for 1 min; centrifuge at 4000r/min for 5 min:
Take 1:5mL of supernatant for purification:
7:1:3 Tea and spices
Weigh 2g (accurate to 0:01g) of the sample into a 50mL centrifuge tube, add 10mL of water, and vortex for 30 seconds to completely wet the sample; then add 10mL of acetonitrile, vortex and extract for 3 minutes; add 5g of chlorine to the centrifuge tube: sodium, vortex for 1 min; centrifuge at 4000r/min for 5 min:
Take 1:5mL of supernatant for purification:
7:2 Purification
7:2:1 Vegetables, fruits, edible fungi, vegetable oils
Place 1:5 mL of vegetable (except vegetables with high pigment content such as leeks) or fruit sample supernatant into a 2 mL centrifuge tube containing 50 mg PSA and 150 mg anhydrous magnesium sulfate; place 1:5 mL of vegetable sample supernatant with high pigment content Place into a 2mL centrifuge tube containing 40 mg PSA, 15 mg GCB and 150 mg anhydrous magnesium sulfate; place 1:5 mL edible fungus or vegetable oil sample supernatant into a 2 mL centrifuge tube containing 50 mg C₈ and 150 mg anhydrous magnesium sulfate; vortex Spin for 30 seconds, centrifuge at 5000r/min for 5 minutes, and pass the supernatant through an organic filter membrane for HPLC-MS/MS detection:
7:2:2 Cereals, oilseeds, nuts
Put 1:5mL of supernatant into a 2mL centrifuge tube containing 50mg Cis and 150mg anhydrous magnesium sulfate; vortex for 30s, centrifuge at 5000r/min for 5 minutes, and pass the supernatant through an organic filter membrane for HPLC-MS/ MS detection:
7:2:3 Tea and spices
Put 1:5mL of the supernatant into a 2mL centrifuge tube containing 50mg PSA, 20mg GCB and 150mg anhydrous magnesium sulfate; vortex for 30 s and centrifuge at 5000 r/min for 5 min: Pass the supernatant through an organic filter membrane for HPLC-MS/MS detection:
7:3 Instrument reference conditions
7:3:1 Liquid Chromatography Reference Conditions
a) Chromatographic column: Ci column, 100mm×2:1mm (inner diameter), 1:7μm or corresponding type of chromatographic column;
b) Column temperature: 45℃;
c) Mobile phase: A is acetonitrile, B is 0:2% formic acid solution;
d) Injection volume: 5pL;
e) Flow rate: 0:3mL/min;
f) Mobile phase and gradient elution conditions: see Table 1:
7:3:2 Mass spectrometry reference conditions
a) Ion source type: ESI;
b) Capillary voltage: 3kV;
c) Cone gas: nitrogen, 50L/h;
d) Ion source temperature: 120℃;
e) Drying gas: nitrogen, flow rate 600L/h, temperature 350℃;
f) Collision gas: argon, 0:16mL/min;
g) Scanning method: positive ion scanning;
h) Detection method: multiple reaction monitoring (MRM), monitoring conditions are shown in Table 2:
7:4 Standard working curve
Accurately draw an appropriate amount of chlorfenuron standard working solution (4:4:2), dilute it with blank matrix extract solution, and prepare a mass concentration of 0:002
mg/L, 0:01mg/L, 0:05mg/L, 0:1mg/L, 1mg/L series matrix standard solutions for determination by liquid chromatography-mass spectrometry: Using the measured peak area as the ordinate and the corresponding standard solution mass concentration as the abscissa, draw a standard curve and find the regression equation and correlation coefficient:
7:5 Qualitative and quantitative
7:5:1 Retention time
When comparing the retention time of the chromatographic peak of the target compound in the test sample with the retention time of the chromatographic peak of the component in the corresponding standard solution, the relative error should be within ±2:5%:
7:5:2 Quantitative ions, qualitative ions and product ion abundance ratios
When measuring samples under the same experimental conditions, if the retention time of the detected chromatographic peak is consistent with that of the standard sample, and in the mass spectrum of the sample after subtracting the background, the mass spectrum quantification and qualitative ions of the target compound should appear, and the same detection Batch, for the same compound, if the relative abundance ratio of the qualitative ion and quantitative ion of the target compound in the sample is compared with the standard solution with equivalent mass concentration, and the allowable deviation does not exceed the range specified in Table 3, it can be judged that there is chlorine in the sample: Pyramide:
7:6 Determination
Inject the matrix standard solution and the solution to be tested into the liquid chromatography-mass spectrometer respectively, and use retention time and qualifier ions to determine the quality: The mass concentration of clofenuron in the sample should be within the mass concentration range of the standard working curve, and the maximum concentration exceeding the standard working curve should be Dots should be diluted before analysis: Quantified using external standard method:
7:7 Blank test
Except that no sample is added, parallel operations shall be carried out in accordance with the provisions of 7:1 to 7:6:
8 Result calculation
The residual amount of chlorfenuron in the sample is measured as mass fraction w, and the unit is expressed in milligrams per kilogram (mg/kg), and is calculated according to formula (1):
9 Precision
9:1 Under repeatability conditions, the absolute difference between two independent measurement results does not exceed the repeatability limit (r): The data for the repeatability limit (r) is:
a) When the content is 0:01mg/kg, the repeatability limit (r) is 0:0030;
b) When the content is 0:05mg/kg, the repeatability limit (r) is 0:012;
c) When the content is 0:5mg/kg, the repeatability limit (r) is 0:11:
9:2 Under reproducibility conditions, the absolute difference between two independent measurement results does not exceed the reproducibility limit (R): The data for the reproducibility limit (R) is:
a) When the content is 0:01mg/kg, the reproducibility limit (R) is 0:0044;
b) When the content is 0:05mg/kg, the reproducibility limit (R) is 0:015;
c) When the content is 0:5mg/kg, the reproducibility limit (R) is 0:16:
10 others
The limit of quantitation of this method is 0:01mg/kg:
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