HOME   Cart(0)   Quotation   About-Us Tax PDFs Standard-List Powered by Google www.ChineseStandard.net Database: 189760 (30 Nov 2024)

GB/T 18932.23-2003 PDF in English


GB/T 18932.23-2003 (GB/T18932.23-2003, GBT 18932.23-2003, GBT18932.23-2003)
Standard IDContents [version]USDSTEP2[PDF] delivered inName of Chinese StandardStatus
GB/T 18932.23-2003English90 Add to Cart 0-9 seconds. Auto-delivery. Method for the determination of oxytetracycline, tetracycline, chlortetracycline and doxycycline residues in honey -- LC-MS-MS method Valid
Standards related to (historical): GB/T 18932.23-2003
PDF Preview

GB/T 18932.23-2003: PDF in English (GBT 18932.23-2003)

GB/T 18932.23-2003 GB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 67.180.10 X31 Method for the determination of oxytetracycline, tetracycline, chlortetracycline and doxycycline residues in honey - LC-MS-MS method ISSUED ON. DECEMBER 26, 2003 IMPLEMENTED ON. JUNE 1, 2004 Issued by. General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China; Standardization Administration of the People’s Republic of China. Table of Contents Foreword ... 3  1.  Scope ... 4  2.  Normative references... 4  3.  Principle ... 4  4.  Reagents and materials ... 5  5.  Apparatuses ... 6  6.  Preparation and storage of sample ... 6  7.  Determination steps ... 7  8.  Result calculation... 9  9.  Precision ... 9  Annex A (Informative) Reference material’s total ion chromatogram ... 11  Annex B (Informative) Recovery rate ... 12  Foreword This Part of GB/T 18932 modifies and adopts Canadian Standard ACC-042-V1.0 Determination of Tetracycline Residue in Honey - LC-MS-MS Method. The main modifications are as follows. — Eluent is changed from methanol to ethyl acetate; — Carboxylic acid anion exchange column is added for purification; — The single quadrupole mass spectrometry detector is changed to tandem quadrupole mass spectrometry detector. Annex A and B of this Part are informative. This Part was proposed by State Administration for Quality Supervision and Inspection and Quarantine (AQSIQ). This Part shall be under the jurisdiction of All China Federation of Supply and Marketing Cooperatives. Drafting organization of this Part. Qinhuangdao Entry-Exit Inspection and Quarantine Bureau of PRC. The main drafters of this Part. Pang Guofang, Zhang Jinjie, Cao Yanzhong, Jia Guangqun, Fan Chunlin, Liu Yongming, Li Xueming, and Shi Yuqiu. This Part is issued as a national standard for the first time. Method for the determination of oxytetracycline, tetracycline, chlortetracycline and doxycycline residues in honey - LC-MS-MS method 1. Scope This Part of GB/T 18932 specifies the method for the determination of oxytetracycline, tetracycline, chlortetracycline and doxycycline residues in honey. This Part is applicable to the determination of oxytetracycline, tetracycline, chlortetracycline and doxycycline residues in honey. Detection limits for the method in this Part. for oxytetracycline and tetracycline, it is 0.001 mg/kg ; for chlortetracycline and doxycycline, it is 0.002 mg/kg. 2. Normative references The articles contained in the following documents have become the articles of this Part when they are quoted in this Part of GB/T 18932. For the dated documents so quoted, all the subsequent modifications (excluding all corrections) or revisions made thereafter do not apply to this Part. However, the parties who reach an agreement according to this Part are encouraged to study whether the latest versions of these documents may be used. For the undated documents so quoted, the latest versions (including all modification sheets) apply to this document. GB/T 6379 Precision of test methods - Determination of repeatability and reproducibility for a standard test method by interlaboratory tests (GB/T 6379-1986, neq ISO 5725.1981) GB/T 6682 Water for analytical laboratory use - Specification and test methods (GB/T 6682-1992, neq ISO 3696.1987) 3. Principle For tetracycline antibiotic residue in the specimen, use 0.1 mol/L Na2EDTA-Mcllvaine (pH=4.0±0.05) buffer solution to extract the extraction solution; after centrifugation, purify the supernatant with Oasis HLB or equivalent solid phase extraction column and anion exchange column; determine the tetracycline antibiotics in the specimen; Use liquid chromatography - tandem mass spectrometer to determine. And adopt the external oxytetracycline, tetracycline, chlortetracycline and doxycycline (4.15); respectively use methanol to prepare 0.1 mg/mL standard stock solutions. Store the stock solutions in -18°C. 4.17 Matrix mixed standard working solutions of oxytetracycline, tetracycline, chlortetracycline and doxycycline. according to needs, pipette appropriate standard stock solutions of oxytetracycline, tetracycline, chlortetracycline and doxycycline (4.16); use blank sample extracting solution to dilute to be the matrix mixed standard working solutions of appropriate concentrations; store the matrix standard solutions at 4°C; it may be used in three days. 5. Apparatuses 5.1 LC-tandem quadrupole mass spectrometer, equipped with electrospray ionization source. 5.2 Analytical balances. 2 balances of which the sensitivity is 0.1 mg and 0.01 g respectively. 5.3 Liquid mixer. 5.4 Solid phase extraction vacuum device. 5.5 Liquid reservoir. 50mL. 5.6 Micro-syringe. 25uL and 100uL. 5.7 Graduated sample tube. 5mL, precision is 0.1mL. 5.8 Vacuum pump. vacuum degree shall reach 80kPa. 5.9 Centrifuge tube. 50mL. 5.10 Flat-bottomed flask. 100mL. 5.11 pH meter. measurement precision is ±0.02. 6. Preparation and storage of sample 6.1 Sample preparation For non-crystallized laboratory sample, stir it evenly; For crystallized sample, in a enclosed circumstance, place it in the water bath at not more than 60°C; warm it; oscillate it; after it is totally melted, stir it; rapidly cool it to room temperature. Take 0.5 kg as the sample. Place the prepared sample in the sample flask, seal and mark it. oxytetracycline, tetracycline, chlortetracycline and doxycycline are shown in Table 3. If the difference exceeds the repeatability limit, it shall discard the test results and carry out two independent tests again. 9.2 Reproducibility Under reproductive conditions, the absolute difference between two independent test results shall not exceed reproducibility limit (R). The content range and reproducibility equation of oxytetracycline, tetracycline, chlortetracycline and doxycycline are shown in Table 3. Table 3 Content range AND repeatability and reproducibility equations Name Content Range (mg/kg) Repeatability Limit r Reproducibility Limit R Oxytetracycline 0.002~0.100 lgr=0.9668lgm - 0.8686 lgR=1.0096lgm - 0.6597 Tetracycline 0.002~0.100 lgr=0.9484lgm - 0.8370 lgR=1.1611lgm - 0.2317 Chlortetracycline 0.002~0.100 lgr=0.8395lgm - 1.0872 lgR=0.9060lgm - 0.8136 Doxycycline 0.002~0.100 lgr=0.9209lgm - 0.8462 lgR=0.9899lgm - 0.6504 Note. m is the arithmetic mean value of two test results. Annex B (Informative) Recovery rate The test data od adding concentrations and average recovery rates of oxytetracycline, tetracycline, chlortetracycline and doxycycline are shown in Table B.1. Table B.1 Test data of adding concentrations and average recovery rates of oxytetracycline, tetracycline, chlortetracycline and doxycycline Drug Name Adding Concentration / (mg/kg) Average Recovery Rate / (%) Oxytetracycline 0.002 0.010 0.050 0.100 88.0 95.3 93.6 95.8 Tetracycline 0.002 0.010 0.050 0.100 81.9 82.6 84.5 89.3 Chlortetracycline 0.002 0.010 0.050 0.100 87.2 86.0 86.6 90.8 Doxycycline 0.002 0.010 0.050 0.100 85.2 85.3 86.8 87.9 ......
 
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.