1、中华人民共和国出入境检验检疫行业标准SN/T 1952-2007 进出口粮谷中戊睡醇残留量的检测方法气相色谱-质谱法Determination of tebuonazoe residues in cereals for import and export-GC-MS method 2008-03-01实施发布中华人民共和国国家质量监督检验检查主总局, ,F P 、! r 卢、也二J、甸、1俨SN/T 1952-2007 前言本标准的附录A为资料性附录。本标准由国家认证认可监督管理委员会提出并归口。本标准起草单位:中华人民共和国山东出入境检验检疫局。本标准主要起草人:李立、睛涛、李征、尹大路、曹
2、鹏。本标准系首次发布的出入境检验检疫行业标准。I 、SN/T 1952-2007 1 范围进出口粮谷中戊瞠醇残留量的检测方法气相色谱-质谱法本标准规定了粮谷中戊哇醇残留量的气相色谱-质谱检测方法。本标准适用于玉米、小麦中戊哇醇残留量的检测和确证。2 方法提要试样用乙酸乙醋提取，用石墨碳/氨基混合固相萃取柱净化，气相色谱-质谱法测定，外标法定量。3 试剂和材料除另有规定外，试剂均为色谱纯，水为超纯水。3. 1 乙酸乙醋:优级纯。3.2 正己皖:优级纯。3.3 乙睛:优级纯。3.4 甲苯:优级纯。3.5 丙酣:优级纯。3.6 无水硫酸铀:分析纯，650C灼烧4h，冷却后储于密封瓶中备用。3. 7
3、戊嗖醇标准品:Tebuconazole,C16 HzzCIN3 ,CAS NO. 107534-96-3，纯度:大于等于98%。3.8 戊哇醇标准储备液:称取造量戊瞠酶标准品，用正己烧配制成1.0 mg/mL的标准储备液，Ooc_ 4C保存。3.9 戊瞠醇标准工作溶液z根据需要，用正己皖将储备液稀释成适当浓度的标准工作液，0C-4C保存。3. 10 Envi-Carb/LC-NHz固相萃取柱:500mg/250 mg，或相当。4 仪器和设备4. 1 气相色谱-质谱联用仪:配有电子轰击离子源(EI源)。4.2 粮谷粉碎机。4.3 旋转蒸发仪。4.4 高速均质器:20000r/mino 4.5 离
4、心管:100mL。4.6 滤膜:0.45m。5 试样的制备与保存取有代表性样品约500g，用粉碎机全部粉碎开通过2.0mm圆孔筛。混匀，装入洁净的容器内，密闭，标明标记。OOC-4C保存。在抽样和制样的过程中，应防止样品受到污染和发生残留物含量的变化。1 SN/T 1952-2007 6 测定步骤6. 1 提取称取10g试样(精确至0.01g)于100mL离心管中，加入50mL乙酸乙醋及10g无水硫酸锅，于10 000 r/min均质提取1min，离心3min，将提取液移入250mL旋转蒸发瓶中。离心管中残渣再用2X30 mL乙酸乙醋提取，提取液井人旋转蒸发瓶中，于40C水浴中旋转蒸发至近干，
5、用2mL甲苯十乙睛。十3)搭解。6.2 净化用10mL甲苯十乙睛。十3)预淋洗Envi-Carb/LC-NHz固相萃取柱，注人提取液(6.1)，用20mL 甲苯+乙睛0+3)溶液分三次洗脱，洗脱液于40C水浴中旋转蒸发至约1mL，氮气吹干，用2mL丙酣+正己皖(1十1)溶解，过滤膜，供气相色谱-质谱测定。6.3 测定6.3. 1 气相色谱质谱条件a) 色谱柱:DB-35MS石英毛细管柱，30mXO. 25 mm(内径)，0.25m(膜厚h30 C /min _ _ _ 10C /m b) 柱温:70 C 0 min)一一一一250C一一一一:305C(10 min); d 进样口温度:250
6、C ; d) 辅助加热器:280C;e) 离子源温度:230.C;f) 四极杆温度:150C; g) 载气z氮气，纯度大于等于99.999%,1 mL/min; h) 进样量:2L;i) 进样方式:不分流;j) 电离方式:EI;k) 电离能量:70eV; D 选择离子(m/z):125、127、250、252;定量离子:250。6.3.2 气相色谱质谱测定根据样液中被测物含量情况，选定浓度相近的标准工作溶液，对标准工作搭液与样液等体积参插进样测定，标准工作溶液和待测样液中戊嗖醇的响应值均应在仪器检测的线性范围内。如果样液与标准工作溶液的选择离子色谱图中，在相同保留时间有色谱峰出现，并且在扣除背
7、景后的样品质量色谱中，所选离子均出现，所选择离子的丰度比与标准品对应离子的丰度比，其值在允许范围内(见表1)。在6.3.1条件下，戊嗖醇保留时间为11.0 min，其监测离子(m/z)为m/z125、127、250、252(其丰度比为100: 35 : 75 : 25)对其进行确证E根据定量离子m/z250对其进行外标法定量。戊唾醇标准物的气相色谱-质谱总离子流色谱图和全扫描质谱图参见附录A中图A.1和A.2.相对离子丰度/%允许的相对偏差/%7 结果计算与表述表1使用定性气相色谱-质谱时相对离子丰度最大窑许误差50 20-50 10-20 10 土10士15士20士50用色谱数据处理机或按式
8、。)计算样品中戊哩醇残留量，计算结果应扣除空白值。2 A. c. V X=-一-一.(1 ) As. m 式中:X一一试样中戊瞠醇残留量，单位为毫克每千克(mg/kg); A一一样品溶液中戊瞠酶的峰面积3As一一戊瞠醇标准工作需液的峰面积;V一一样品溶液最终定容体积，单位为毫升(mL);C一-戊哇薛标准工作液的浓度单位为微克每毫升(g/mL);m一一最终样液代表的试样质量，单位为克(g)。8 测定低限和回收率8. 1 测定低限本方法戊瞠醇的测定低限为0.010mg/kg。8.2 回收率玉米:一一添加水平0.010mg/峙，回收率在84.8%-106.4%; 一一添加水平0.020mg/峙，回收
9、率在82.1%-107.8%; 一一-添加水平0.050mg/峙，回收率在89.1%-120.0%。小麦:一一添加水平0.010mg/陆，回收率在84.7%-100.9%; 一一添加水平0.020mg/峙，回收率在82.1%-110.6%; 一一添加水平O.050 mg/kg，回收率在83.1%-103.5%。SN/T 1952-2007 3 SN/T 1952-2007 附录A(资料性附录)戊瞌醇标准溶渣的选择离子流固2咐山-m-一，户，、-_., - . 125 70 83 67 4 9. 35 9. 40 9. 45 9. 50 固A.l戊瞌醇标准品的选择离子色谱固0_世.87咽1)!0
10、7O:S:I民.0号-，260 固A.2戊睡醇标准晶质谱固332346356 SN/T 1952-2007 Fore word Annex A of this standard is an informative annex. This standard was proposed by and is under the charge of the Certification and Accreditation Admin stration of the Peoples Republic of China. This standard was drafted by YanTai Entry-Ex
11、it Inspection and Quarantine Bureau of the Peoples Re public of China. This main drafters of this standard are: LiLi, SuiTao, Li Zheng , Yin Da Lu , CaoPeng. This standard is a professional standard for entry-exit inspection and quarantine which is promulga ted standard for the first time. Note: Thi
12、s English version , a translation from the Chinese text, is solely for guidance. 5 SN/T 1952-2007 Determination of tebuonazoe residues in cereals for import and export-GC-MS method 1 Scope This standard specifies the method of sample preparation and determination of Tebuonazoe residues in cereals bg
13、as chromatography-mass spectromet叩.This standard is applicable to the determination and confirmation of Tebuonazoe residues in maize and wheat. 2 Principle The test sample is extracted bethyl acetate, c1eaned up by Envi-Card/LC-NH2 solid phase extraction column. The determination and confirmation is
14、 made bGC-MS， using external standard method. 3 Reagents and materials Unless otherwise specified,all the reagents used should be chromatography pure. Wateris redis tilled water. 3.1 Ethly acetate:first grade pure. 3. 2 n-Hexane: fi rst grade pure. 3.3 Acetonitrile:first grade pure. 3.4 Toluene: fir
15、st grade pure. 3.5 Acetone:first grade pure. 3.6 Anhydrous sodium sulfate:Analytically pure, ignite for 4 h at 650t ,and keep in a tightly con taner. 3.7 Tebuonazon standard:C16H22CI陀，CASNO. 107534-96-3，purity注98%.3.8 Tebuonazon standard stock solution: Weigh an adcquate. amount of tebuonazon standa
16、rd, dis-6 一一-一一一-一二-卢-一一一一一一一-一SN/T 1952-2007 solve in n-hexane to prepare a solution of 1. 0 mg/mL as the standard stock solution, stored at ot-4C. 3.9丁ebuonazonstandard working solution: Acoording to the requirement , prepare a standard working solution by diluting the stock solution with n-hexane
17、, stored at ot -4t. 3.10 Envi-Card/LC-NH2 solid phase extraction column:500 mg/250 mg or equivalent. 4 Apparatus and equipment 4.1 Gas chromatographequipped with EI. 4.2 Grind. 4. 3 Rotary vacuum evaporator. 4.4 High speed homogenizer:20 000 r/min. 4.5 Centrifuge tube: 100 mL. 4.6 Filter:O.45 um. 5
18、Prepare and storage of the test sample Take representation approximately 500 9 of sample. Grind with a grinder and pass through a 2. 0 mm round-hole sieve. Mix thoroughly and placed in clean container, sealed and labeled , as the test sam ple,stored at 0C -4C. White sampling and sample preparation,
19、precaution must be taken to avoid contamination or any factors which may cause the change of residue content. 6 Procedure 6. 1 Extraction Weigh 10 9 of the test sample (accurate to O. 01 g) into a 100 mL centrifuge tube, add 50 mL of ethyl acetate and 10 9 anhydrous sodium sulfate. Extract for 1 min
20、 in a speed of 10 000 r/min,centrifuge for 3 min. Tranact the extract into a 250 mL rota时concentratebottle. Extract the residue with 2 x 30 mL ethI acetate, combine the extract and evaporate on a rota叩evaporator at 4OC to near dryness. Add 2 mL toluene-acetoritrile( 1 + 3) to dissolve the residue. 7
21、 SN/T 1952-2007 6. 2 Cleaning up Rinse the Envi-Carb/LC-NH2 solid phase extraction column with 10 mL toluene-acetonitrile(1 + 3). Pure the exteact(6. 1) into the column , then elute the column three times with 20 mL toluene-aceton trile(1 +3) ,evaporate the eluates to臼1mL bya rota叩evaporatorat 40t ,
22、 dried bblowing nitro gen. Oissolve the residue with 2 mL acetone-n-hexane , passing through a 0.45m filter, the solu tion is ready for GC-MS determination and confirmation. 6. 3 Oetermination 6. 3. 1 GC-MS operatingndition a) GC column : 08-35, Fused silica capillary column , 30 m x O. 25 mm (i. d.
23、 ), O. 25m (film thick ness); 30t/min _ 10t/min b) Column temperature: 70t (v)一一-一:=250t一一一一:305t(10 min) ; c) Injector temperature: 250t ; d) Interface temperature: 280t ; e) lon source temperature:230t ; f) Ouadropole temperature: 150t; g) Carrier gas: Helium, purty注99.999%，1 mL/min; h) Injection
24、volume:2L; i) Injection mode: splitless; j) Electron ionization: EI; k) lonization energ:70eV; 1) Monitor (m/z): qualified by 125,127 ,250 ,252 , quantitied by 250. 6.3.2 Ouantitation and qualification by GC-MS. Select appropriate standard working solution with similar concentration level to that in
25、 sample solu tion, The standard working solution should be injected before and between the injections of the sam ple solutions with same injection volume. The response value of tebuonazoe in the standard working 8 SN/T 1952-2007 solution and sample solution should be within the linear range of the i
26、nstrumental detection. Permitted tolerance for similarity of relative abundance ratio is listed as table 1. When retention time of target peak is according with that of standard solution, postitive samle will be proved based on selected monitoring ions(m/z)125,127 ,250 ,252 (relative abundance ratio
27、: 100: 35: 75: 2日，with (m/z) 250 for quantitation. Under chromatographic condition above (6.3.门，rention time of te buonazon standard is 11.0 min, GC-MS selected ion chromatogram and mass spectrum of the te buonazon standard are shown respectively as figure A. 1 and A. 2 in annex A. Table 1-Maximum p
28、ermitted tolerance for relative ion intensities using a 阳ngeof mass spectrometric techniques Relative intensity/% GC-MS/EI(relative)/% 50 士1020-50 土157 Calculation and expression of the result 10-20 士2010 士50Calculate the content of fipronil residue in the test sample bGC-MS data processor or accord
29、ing to formula (1). The blank value should be subtracted from the result of calculation. A c. V x=一一一一(1 ) As. m where X -the residue content of tebuonazoe in the test samp怡，mg/kg; A -the peak height of tebuonazoe in the sample solution; As-the peak height of tebuonazoe in the standard working solut
30、ion; c-the concentration of tebuonazoe in the standard working solution，g/mL; V-the final volume of the sample solution, mL; m-the corresponding mass of the test sample representing the final sample solution, g. 8 limit of determination and revery 8.1 The limit of determination of this method is 0.0
31、10 mg/kg. 8. 2 Recovery In maize: 一0.010mg/阅，the recovery 84.8-106.4%; 一O.020 mg/kg, the recove叩82.1-107.8%; 一0.050mg/闸，the recove叩89.1-120.0%.9 SN/T 1952-2007 In wheat: -0.010 mg/kg, the recove叩84.7-106.4%; 一0.020mg/kg, the recove叩82.1-110.6%;一0.050mg/闸，the recovery 83. 1-103.5%. 10 2.0 0.2 Annex A
32、 (informat ive) GC-MS total ion chromatogram of the standard SNjl 1952-2007 8.80 8.85 8.90 8.95 9:00 9.05 9:10 9.15 9:20 9.25 9.30 9.35 9.40 9.衍9.50Figure A. 1-GC-MS total ion chromatogram of the tebuonazoe standard 70 83 67 125 D_回扣息也Q.I$77. 哺lG7O:3CW抠:)1.0.1$尊2，.、260 332346356 405 Figure B. 1-Mass spectrum of the tebuonazoe standard hCON-NmFHZm 中华人民共和国出入境检验检疫行业标准进出口粮谷中戊睡醇残留量的检测方法气相色谱-质谱法SN/T 1952-2007 * 中国标准出版社出版北京复兴门外三里河北街16号邮政编码:100045网址电话:6852394668517548 中国标准出版社秦皇岛印刷厂印刷* 开本880X12301/16 印张1字数24千字2007年11月第一版2007年11月第一次印刷印数1-2000* 书号:155066. 2-18234 定价10.00元SN/T 1952-2007
