1、中华人民共和圄出入境检验检疫行业标准SN/1734-2006 进出口水果中4，6皿二硝基邻甲酣残留量的检验方法气相色谱串联质谱法Inspection of 4 ，6帽dinitro吃Eresidues in f仕ru川it臼sfor import and export-GC心-MSmethod 2006-01-26发布060712000070 2006-08-16实施中华人民共和国发布国家质量监督检验检瘟总局本标准的附录A为资料性陪录。阳.L. 皿目U昌本标准由国家认证认可监督委员会提出并归口。本标准起草单位:中华人民共和自深圳出入境检验检疫局。本标准主要起草人:谢丽琪、蓝芳、靳保辉、蔡伊娜、
2、吴卫东。本标准系首次发布的出人境检验检疫行业标准。SN/T 1734-2006 工SN月17342006进出口水果中4，6-二硝基邻申盼残留量的检验方法气相色谱串联质谱法1 茹围本标准规定了水果中4，6币二硝基邻甲酷(DNOC)残留量检验的抽样、船样和气相色谱-质谱检验方法。本标准适用于苹果、梨中4，6-二硝基邻甲勘残留莹的检验。2 抽样和制样2. 1 检验社以不超过1500件为一检验批。肉一检验批的商品应具有相间特征，如:包装、标记、产地、规格和等级等。2.2 抽样数量见表1.2.3 抽样方法批量件数1-25 26-100 101-250 251-1500 表1抽样数量最低抽样件数1 5 1
3、0 15 按2:2规定的抽样件数随机抽取，逐件开启。每件至少取500g作为原始样品，原始样品总量不得少于2问。加封后，标明标记，及时送实验室。2.4 试样制备将所取原始样品缩分出1kg，取可食部分，经组织捣碎机捣碎均匀，均分成两份，装人沽净容器内，作为试样，密封并标明标记。2.5 试样保存将试样于一50C以下避光保存。在搞样和制样过程中，必须防止样品受到污染或发生残留物含量的变化。3 测定方法3. 1 方法提要水果样品中4，6-二硝基邻甲酷残留物用二氧申;院提取，吹氮至于后以乙腊溶解，用N(特丁基二甲基硅)-N-甲基三氟乙酷胶(MTBSTFA)衍生化，用气相色谱白质谱担tl定，外标法定量。3.
4、2 试剂材料除另有规定外，厨有试剂均为分析纯，水为去离子水。3.2.1 二氧甲:民z优级纯。3.2.2 乙腊:GC农药残留级。1 SN/T 1734 2006 3.2.3 元水硫酸铀z经6500C灼烧4h，置于干燥器中备用。3.2.4 4，6币二硝基邻甲勘标准品:纯度99%。3.2.5 衍生化试剂N-(特丁基二甲基硅)-N甲基三氟乙酷肢(MTBSTFA):纯度99%。3.2.6 4，6-工硝基邻甲酷储备液z准确称取10mgDNOC标准品，用乙腊溶解并配制成浓度为100mg/L的标准储备蔽，可在冰箱中OOC40C保存3个月3根据需要再用乙腊将标准储备被稀释成适当浓度的标准工作液，可在冰箱中OOC
5、40C保存1个月。3.3. 1 3.3.2 3.3.3 蘸涡混合器。3.3.4 吹氮浓缩仪。3.3.5 政璃离心管:15mLo 3.3.6 培养箱。3.4 测定步骤3.4. 1 摄取称取制备好的均匀样品约1二氯甲烧(3.2.1)5mL , 人另一个15mL离心管中，5 min，将二氧甲婉转移氮气流吹至近千。100LI在TBSTFA(3.2.日，封口，80oC下恒温街生化1ho标准工作液同样也加入100IlLMTBSTFA(3. 2. 5)，封口，在上述条件下进行衍生化。将衍生化后的溶液转人进样瓶中，供气相色谱-质谱联用仪分析，外标法定量。3.4.3 测定3.4.3. 1 色谱条件a) 色谱柱:
6、HP-5MS b) 色谱柱握度:1000C c) 进样口温度:210oC;d) 传输线温度:250oCe) 载气z氮气，纯度f) 进样量:1L;g) 进样方式:h) k) 1) 溶剂延迟:5mino 3.4.3.2 气相色谱质i普测定(20 min); 根据样品中4，6二硝基邻甲酷含量情况，选择与样品峰面积响应相近浓度的标准工作溶液。衍生化盾的标准工作溶液和样品中4，6-二硝基邻甲酣衍生物的响应值均应在仪器检测的线性蓓围内。对衍生化后标准工作溶液和样品等体积参插进行测定，在上述色谱条件下，4，6币二硝基邻申酣衍生物的保留时间约为9.31min，并根据监测离子的相对丰度比进行确定，标准品SIM色
7、谱图及全扫描质谱酿参见附录A中围A.1、图A.2o3.4.4 空白试验除不加试样外，按上述测定步骤进行。3.4.5 结果计算和表述按式(1)计算试样中4，6-二硝基邻甲酷的含量，计算结果需扣除空白值。式中zx一一样品中4，6-=A一一样液中4，6一4 测定f13:限和自收率4. 1 测定低限梨和苹果的测定低限为4.2 回收率4，6-二硝基邻甲4，6-二硝基邻甲4，6-二硝基邻甲X一生江三兰主-AsXm SN月1734-2006( 1 ) 3 SN/T 1734-2006 附录A资料性附亵)4，6刷工硝基邻咱酣标准品-MTBSTFA衍生物气相色谱-质谱图Abundance 7 000 4，6一二
8、硝基邻甲盼MTB但苦A衍生物6 000 / 5 000 4 000 3 000 2 000 1 000 8.40 8.60 8.80 9.00 9.20 9.40 9.60 9.80 10.00 10.20 10.40 10.60 10.80 .11.00 min 图A.10.5 mg/川，6-工硝基邻阳酣M四STFA衍生物的SIM色谱罔Abundance 255 28 000 24 000 20 000 16 000 12 000 209 8 000 239 179 4 000 o m/z 170 180 190 200 210 220 230 240 250 260 图A.20.5 mg/
9、L 4，6翩二硝基邻甲酣MTBSTFA衍生物SIM殷谱图4 SN/T 1734 2006 Foreword Annex A of this standard is an informative annex. This standard was proposed by and is under the charge of Certification and Accreditation administra幡tion of the Peoples Republic of China. The standard was drafted bShenzhen Entry-Exit Inspecti an
10、d Quarantine Bureau of the Peoples Republic of China. The main drafters of this standard are Xie Liqi , Lan Fang , Jin Baohui , Cai Yina , Wu Weidong. This standard is a professional standard for entry幡exitinspection and quarantine promulgated for the first time. Note: This 巨nglishversion , a transl
11、ation from the Chinese text,is solely for guidance. 5 SN/T 1734一2006Inspection of 4, 6-dinitro-cresol residues in fruits for import and export-GC-MS method 1 Scope This standard specifi.es the This standard is applicable to the ification and grade , should be the same. 2. 2 Quantity of Sample taken
12、See Table 1. 2.3 Sampling procedure bgas chro-in pear and apple. , mark, origin , spec-A number of packages specified in 2.2飞牙苍tkenat random ar.-ned one bone. The sample taken a$ the primary sample from each package should be at least 500 g.丁hetotal weight of all the primary samples should not be le
13、ss thim 2闸，which shall be sealed , labeled and sent to laboratory in time. 2. 4 Preparation of t.est sample The combined primary samples. is reduced to 1峙，the edible portions are blended and then divided 6 SN/T 1734 2006 into two equal portions. Each portion is placed in a clean container as the tes
14、t sample, which is sealed and labeled. 2. 5. Storage of sample 丁hetest sample should be stored below - 5C and kept away from light. During sampling and prepa-ration of sample , the change of residue 3 Method of 3.1 Principle The residue 4,6-dinitro-cresol concentrating the tograph equipped with 3. 2
15、 Reagents and Unless otherwise specified , all eagents should be of 3.2.1 Dichloromethane: GR. 3.2.2 Acetonitrile: Grade 3.2.3 Anhdrous 3.2.4 4,6-Dinitro-cresol 3.2.5 MTBSTFA: Purity 3. 2. 6 DNOC standard standard stock solution of 100 erator between OoC _40C for 3 factors that macause After by a ga
16、s chroma-water is deionized water. closed container. in acetonitrile to form a be preserved in the refrig solution with acetonitrile to the req川redconcentration as the standard working solution, which can be preserved in the refrigera tor between OoC _40C for 3 months. 3. 3 Apparatus and equipment 3
17、.3. 1 Gas chromatograph , equipped with mass detector. 7 SN/T 1734-2006 3. 3. 2 Centrifuge. 3.3.3 Mechanical Shaker. 3.3.4vaporator. 3.3.5 Vitreous centrifuge tube: 15 mL. 3.3.6 Oven. 3. 4 Procedure 3. 4. 1 Extraction Weighing 1 9 (accurate to 0.01 g) of the test sample into a 15 mL centrifuge tube
18、, then adding 3 9 anhdrous sodium sulfate (3.2.3) and 5 mL dichloromethane (3. 2. 1) into the centrifuge, blending on a mechanical shaker for 3 min, centrifuging for 5 min (2000 r/ min). Transferring the upper di chloromethane extract into another 15 mL centrifuge tube. Extract in twice and concentr
19、ating the ex tract to dry under nitrogen at 50oC. 3. 4. 2 derivatization O. 4 mL acetonitrile (3. 2. 2) was added into centrifuge tube to dissolve the sample , then 100L deri vatization reagent (3.2.5) was added to react with the sample at 80巳.And another one was added to react with the standard wor
20、king solution at 80oC. The derivat勺ationwas carried out in a dry cabi net for 1 h. The solution containing the derivatives was determinate bGC-MS， using external stand ard method. 3. 4. 3 Determination 3. 4. 3. 1 GC operating conditions a) Column: HP-5MS fused quartz capillary column , 30 m X 0.25 m
21、m X 0.25m; 30t/min .，.，.，. ., 5t/min _.，.，. 10t/min b) Column temperature: lOOoC (1 min)一一一一.:.:.:.+180t (1 min)一一一一205C一一一一260t (20 min) ; c) Injection port temperature: 2100C ; d) GC/MS interface temperature: 250t ; 8 SN/T 1734-2006 e) Carrier gas: Helium , Purity注99.999%，1.0 mL/ min; f) Injection
22、 volume: 1L; g) Injection mode: Splitless , o min split valve off; 1 min split valve on. h) lonization mode: EI; lonization energy: 70 eV; j) Acquisition mode: SIM; k) Monitoring ions: 255 ,209 ,239 ,179 m/z; quanttative ion: 255 m/z; 1) Solvent delay: 5 min. 3. 4. 3. 2 GC determination According to
23、 the approximate concentration of DNOC in the test sample solution , the standard work ing solution is selected with similar peak area to that of sample solution. The response of DNOC de rivative in the standard working solution and sample solution should be in the linear range of the in strumental
24、detection. The standard working solution should be injected randomly in between the in jections of sample solution of equal volume. MS confirmation is according to the intensity ratio of monitoring ions. Under the above chromatograph conditions, the reaction tlme of DNOC derivative is about 9.31 min
25、. DNOC standard derivative SIM chromatogram and spectrum can be found in Fig A. 1 , Fig A. 2. 3. 4. 4 81ank test The operation of the blank test is the same as that described in the method of determination, but with omission of sample addition. 3. 4. 5 Calculation and expression of result The calcul
26、ation of DNOC content in the sample is according to the following formula , the blank value should be subtracted from the result of calculation: A x cX V x=一一一一一一(2 ) As X m Where X一theresidue content of DNOC in the test sample , mg/ kg; A一一一Peakarea of DNOC derivative in the sample solution; 9 SN/T
27、 1734-2006 As-Peak area of DNOC derivative in the standard working solution; c-the concentration of DNOC in the standard working solution ,mg/L; V一一一thefinal volume of sample solution , mL; m一一-thecorresponding mass of test sample in the final sample solution , g. 4 Limit of determination and recove
28、r 4.1 Limit of Th limit of 4. 2 Recovery DNOC O. 01 mg/阔，the recovery DNOC O. 05 mg/ kg , the DNOC O. 10 mg/ kg , the 10 f巧飞SN/T 1734-2006 Abundance 35 000 30 000 25 000 20 000 15 000 10 000 5 000 Annex A Clnformative) Gas Chromatogram of the DNOC幡MTBSTFAderivatized compound DNOC-1在TBSTFADerivative
29、/ 8.40 8.60 8.80 9.00 9.20 9.40 9.60 9.80 10.00 10.20 10.40 10.6010.80 11.00 Fig A.1 SIM chromatograph of 0; 5 mg/L DNOC standard MTBSTFA derivative Abundance 255 28 000 24 000 20 000 16 000 12 000 209 8 000 239 179 4 000 。m/z 170 180 190 200 210 220 230 240 250 260 Fig A.2 SIM mass spectrum of O. 5 mg/L DNOC standard M丁BSTFAderivative mm OON|守的hFH军中华人民共和国出入境检验检疫行业标准进出口水果中4，6-工硝基邻甲酣残留景的检验方法气相色谱串联质谱法SN月1734-20069非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880X 1230 1/16 印张1字数21千字2006年5月第一版2006年5月第一次印刷印数1一2000定价10.00元9舍书号:155066 2-16834 1734-2006
