GB 31658.3-2021 English PDFUS$139.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email. GB 31658.3-2021: National food safety standard - Determination of baclofen residue in swine urine by liquid chromatography-tandem mass spectrometry method Status: Valid
Basic dataStandard ID: GB 31658.3-2021 (GB31658.3-2021)Description (Translated English): National food safety standard - Determination of baclofen residue in swine urine by liquid chromatography-tandem mass spectrometry method Sector / Industry: National Standard Classification of Chinese Standard: X04 Word Count Estimation: 7,728 Issuing agency(ies): National Health Commission of the People's Republic of China, State Administration for Market Regulation GB 31658.3-2021: National food safety standard - Determination of baclofen residue in swine urine by liquid chromatography-tandem mass spectrometry method---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. National food safety standards Determination of baclofen residues in pig urine Liquid chromatography-tandem mass spectrometry National Standards of People's Republic of China Released by the National Health Commission of the People's Republic of China State Administration for Market Regulation Ministry of Agriculture and Rural Affairs of the People's Republic of China ForewordThis document complies with the provisions of GB/T 1:1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents" Drafting: This document is published for the first time: National food safety standards Determination of baclofen residues in pig urine by liquid chromatography-tandem mass spectrometry1 ScopeThis document specifies the sample preparation and liquid chromatography-tandem mass spectrometry methods for the determination of baclofen residues in pig urine: This document is applicable to the detection of baclofen residues in pig urine:2 Normative reference documentsThe contents of the following documents constitute essential provisions of this document through normative citations in the text: Among them, the cited documents with dates are: Only the version corresponding to the date applies to this document; for undated referenced documents, the latest version (including all amendments) applies to this document: document: GB/T 6682 Specifications and test methods for water used in analytical laboratories3 Terms and definitionsThere are no terms or definitions that need to be defined in this document:4 PrinciplesThe remaining baclofen in the sample was acidified, extracted, purified with a solid phase extraction column, measured by liquid chromatography-tandem mass spectrometry, and quantified by the internal standard method:5 Reagents and materialsUnless otherwise specified, all reagents are of analytical grade and the water is first-grade water that complies with GB/T 6682: 5:1 Reagents 5:1 Acetonitrile (CH3CN): chromatographically pure: 5:1:2 Methanol (CH3OH): chromatographically pure: 5:1:3 Formic acid (HCOOH): chromatographically pure: 5:1:4 Hydrochloric acid (HCl): 5:1:5 Ammonia (NH3:H2O): 5:1:6 Sodium hydroxide (NaOH): 5:2 Solution preparation 5:2:1 10% hydrochloric acid solution: Take 10mL of hydrochloric acid and dilute it with water to 100mL: 5: 2: 0:1% formic acid solution: Take 0:5 mL of formic acid and dilute to 500 mL with water: 5:2% formic acid solution: Take 0:2mL of formic acid and dilute it with water to 100mL: 5:2% formic acid-acetonitrile solution: Take 80mL of 0:2% formic acid solution and add acetonitrile to dilute it to 100mL: 5:2:5 5% ammonia-methanol solution: Take 5 mL of ammonia water and dilute it with methanol to 100 mL: 5:2:6 1mol/L sodium hydroxide solution: Take 4g of sodium hydroxide, dissolve it in water and dilute it to 100mL: 5:3 Standard products 5:3:1 Baclofen (Baclofen, C10H12ClNO2, CAS number: 1134-47-0) content ≥ 99:0%: 5:3:2 Baclofen-D4: content ≥99:0%: 5:4 Preparation of standard solution 5:4:1 Baclofen standard stock solution: Take about 10 mg of baclofen standard, weigh it accurately, and add 1 mL of 1 mol/L sodium hydroxide solution to dissolve it: GB 31658:3-2021 Solution, dilute with methanol to a 10mL volumetric flask to prepare a baclofen standard stock solution with a concentration of 1mg/mL: Store below 4°C to be effective: Period of 4 months: 5:4:2 Baclofen standard intermediate solution (10μg/mL): Precisely measure 100μL of baclofen standard stock solution, put it in a 10mL volumetric flask, and dilute with methanol Release to the mark and prepare a baclofen standard intermediate solution with a concentration of 10 μg/mL: Store below 4°C and has a validity period of 1 month: 5:4:3 Baclofen standard working solution (1μg/mL): Precisely measure 1mL of the baclofen standard intermediate solution, dilute it with methanol to a volume of 10mL bottle, prepare a standard working solution of baclofen with a concentration of 1 μg/mL: Prepare it for immediate use: 5: Baclofen-D4 stock solution (1 mg/mL): Take about 10 mg of baclofen-D4 reference substance, weigh it accurately, and add 1 mol/L sodium hydroxide solution Dissolve in 1 mL, dilute with methanol to the volume of 10 mL volumetric flask, and prepare a baclofen-GD4 stock solution with a concentration of 1 mg/mL: Store it under the following conditions and it is valid for 4 months: 5． Release it into a baclofen-D4 intermediate solution with a concentration of 10 μg/mL: Store below 4°C and has a validity period of 1 month: 5:4:6 Baclofen-D4 working solution (1μg/mL): Precisely measure 1mL of baclofen-D4 intermediate solution, place it in a 10mL volumetric flask, and dilute with methanol Release into baclofen-D4 working solution with a concentration of 1 μg/mL: Prepare now for immediate use: 5:4:7 Mix standard working solution: Precisely measure appropriate amounts of Baclofen standard working solution and Baclofen-D4 working solution, and dissolve them with 0:2% formic acid-acetonitrile: The liquid was prepared to contain baclofen-D410ng/mL, and the baclofen-containing concentrations were 1:0ng/mL, 2:0ng/mL, 5:0ng/mL, 10:0ng/mL, and 25:0ng/mL and 50:0ng/mL series mixed standard working solutions: Prepared and ready for use: 5:5 Materials Mixed strong cation solid phase extraction column, 60mg/3mL, or equivalent:6 Instruments and equipment6:1 Liquid chromatography-tandem mass spectrometer: equipped with electrospray ionization source: 6:2 Analytical balance: sensitivity 0:00001g and 0:01g: 6: Centrifuge: 8000r/min: 6: Vortex oscillator: 6:5 Solid phase extraction device: 6:6 Nitrogen blower: 6:7 pH meter: 6: Centrifuge tube: 50mL: 6:9 Filter membrane: 0:22μm, water phase: 7: Preparation and preservation of samples 7:1 Preparation of samples Take an appropriate amount of fresh or thawed blank or test sample, return to room temperature before use, mix well, if there is turbidity, centrifuge and take the supernatant for later use: a) Take spare test samples as test materials; b) Take a spare blank sample as blank material; c) Take the spare blank sample, add the standard working solution of appropriate concentration, and add the sample as a blank: 7:2 Preservation of samples Test samples or blank samples should be frozen and stored below -18°C as soon as possible:8 Measurement steps8:1 Extraction Take 2:0 mL of the sample, put it into a 50 mL centrifuge tube, add 10 μL of baclofen-D4 working solution, adjust the pH to 2:0 with 10% hydrochloric acid solution, and vortex Vortex to mix, centrifuge at 8000r/min for 5min, and set aside: 8:2 Purification Take the solid phase extraction column and activate it with 3 mL of methanol and 3 mL of water in sequence: Pass all the backup solution through the column and rinse it with 3 mL of water and 3 mL of methanol in sequence: Pump dry for 2 minutes, elute with 6 mL of 5% ammonia-methanol solution, collect the eluent, blow dry with nitrogen in a water bath at 50°C, and use 0:2% formic acid-acetonitrile solution: Dissolve in 1:0 mL, filter through membrane, and measure by liquid chromatography-tandem mass spectrometry: 8:3 Preparation of standard curve Take a series of mixed standards of 1:0ng/mL, 2:0ng/mL, 5:0ng/mL, 10:0ng/mL, 25:0ng/mL and 50:0ng/mL: The working solution is used for liquid chromatography-tandem mass spectrometry determination: Taking the measured characteristic ion mass chromatography peak area ratio as the ordinate, the corresponding standard solution With the liquid concentration as the abscissa, draw a standard curve and find the regression equation and correlation coefficient: 8: Measurement 8:4:1 Chromatographic conditions a) Chromatographic column: C18 (100mm×3:0mm, 1:8μm), or equivalent; b) Column temperature: 35℃; c) Injection volume: 10μL; d) Mobile phase: A is methanol, B is 0:1% formic acid solution, gradient elution conditions are shown in Table 1; e) Flow rate: 0:25mL/min: 8:4:2 Mass spectrometry conditions a) Ionization mode: electrospray positive ion source; b) Detection method: multiple reaction monitoring (MRM); c) Ion source temperature: 150℃; d) Capillary voltage: 3:0kV; e) Desolvation temperature: 500℃; f) Qualitative ion pairs, quantitative ion pairs and their corresponding cone voltages and collision energies are shown in Table 2: 8: 4: Determination method Take the sample solution and standard solution, perform single-point or multi-point calibration, and quantify the chromatographic peak area according to the internal standard method: The response values of chlorfen and baclofen GD4 should be within the linear range of instrument detection: The retention time of baclofen in the sample solution is the same as that in the standard working solution: The retention time deviation of baclofen is within ±2:5%, and the relative ion abundance detected should be the relative abundance of the standard solution with equivalent concentration: Consistent, the allowable deviation should meet the requirements of Table 3: Under the above chromatography-mass spectrometry conditions, the characteristic ion masses of baclofen and baclofen-GD4 standard solution See Appendix A for the chromatogram: 8:5 Blank test Take a blank sample and perform parallel operations using the same measurement steps except that no standard solution is added:9 Calculation and presentation of results10 Sensitivity, accuracy and precision of detection methods 10:1 Sensitivity The detection limit of this method is 0:5ng/mL, and the quantification limit is 1:0ng/mL: 10:2 Accuracy The recovery rate of this method at the added concentration level of 1:0ng/mL~25ng/mL is 70%~110%: 10:3 Precision The intra-batch relative standard deviation of this method is ≤15%, and the inter-batch relative standard deviation is ≤20%: ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB 31658.3-2021_English be delivered?Answer: Upon your order, we will start to translate GB 31658.3-2021_English as soon as possible, and keep you informed of the progress. 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