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ICSX中华人民共和国国家标准GB23200.13—2016代替GB/T23205—2008食品安全国家标准茶叶中448种农药及相关化学品残留量的测定液相色谱-质谱法NationalFoodSafetyStandards—Determinationof448pesticidesresiduesinteaLiquidchromatography-massspectrometry2016-12-18发布2017-06-18实施GB23200.13—2016I目次前言„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„Ⅱ1范围„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„12规范性引用文件„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„13原理„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„14试剂和材料„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„15仪器和设备„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„26试样制备„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„27分析步骤„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„28结果计算和表述„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„49精密度„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„410定量限和回收率„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„4附录A(资料性附录)448种农药及相关化学品中、英文名称、方法定量限、分组、溶剂选择和混合标准溶液浓度表„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„5附录B(资料性附录)448种农药及相关化学品监测离子对碰撞气能量、源内碎裂电压和保留时间14附录C(资料性附录)448种农药及相关化学品多反应监测(MRM)色谱图„„„„„„„„„„24附录D(资料性附录)实验室内相对标准偏差„„„„„„„„„„„„„„„„„„„„„„44附录E(资料性附录)实验室间相对标准偏差„„„„„„„„„„„„„„„„„„„„„„45附录F(资料性附录)样品的添加浓度及回收率的实验数据„„„„„„„„„„„„„„„„46GB23200.13—2016II前言本标准代替GB/T23205-2008《茶叶中448种农药及相关化学品残留量的测定液相色谱-串联质谱法》。本标准与GB/T23205-2008相比,主要变化如下:—标准文本格式修改为食品安全国家标准文本格式;—标准范围中增加“其它茶叶可参照执行”。本标准所代替标准的历次版本发布情况为:—GB/T23205-2008。GB23200.13—20161食品安全国家标准茶叶中448种农药及相关化学品残留量的测定液相色谱-质谱法1范围本标准规定了绿茶、红茶、普洱茶、乌龙茶中448种农药及相关化学品(参见附录A)残留量液相色谱-质谱测定方法。本标准适用于绿茶、红茶、普洱茶、乌龙茶中448种农药及相关化学品残留的定性鉴别,也适用于418种农药及相关化学品残留的定量测定,其它茶叶可参照执行。2规范性引用文件下列文件对于本文件的应用是必不可少的。凡是注日期的引用文件,仅所注日期的版本适用于本文件。凡是不注日期的引用文件,其最新版本(包括所有的修改单)适用于本文件。GB2763食品安全国家标准食品中农药最大残留限量GB/T6682分析实验室用水规格和试验方法3原理试样用乙腈匀浆提取,经固相萃取柱净化,用乙腈-甲苯溶液(3+1)洗脱农药及相关化学品,用液相色谱-串联质谱仪检测,外标法定量。4试剂和材料除另有规定外,所有试剂均为分析纯,水为符合GB/T6682中规定的一级水。4.1试剂4.1.1乙腈(CH3CN,75-05-8):色谱纯。4.1.2甲苯(C7H8,108-88-3):优级纯。4.1.3丙酮(CH3COCH3,67-64-1):色谱纯。4.1.4异辛烷(C8H18,540-84-1):色谱纯。4.1.5甲醇(CH3OH,67-56-1/170082-17-4):色谱纯。4.1.6乙酸(CH3COOH,64-19-7):优级纯。4.1.7氯化纳(NaCl,7647-14-5):分析纯。4.1.8无水硫酸钠(Na2SO4,7757-82-6):分析纯。用前在650℃灼烧4h,贮于干燥器中,冷却后备用。4.2溶液配制4.2.10.1%甲酸溶液:取1000mL水,加入1mL甲酸,摇匀备用。4.2.25mmol/L乙酸铵溶液:称取0.385g乙酸铵,加水稀释至1000mL。4.2.3乙腈-甲苯溶液(3+1):取300mL乙腈,加入100mL甲苯,摇匀备用。4.2.4乙腈+水溶液(3+2):取300mL乙腈,加入200mL水,摇匀备用。4.3标准品农药及相关化学品标准物质:纯度≥95%,参见附录A。4.4标准溶液配制4.4.1标准储备溶液分别称取5mg~10mg(精确至0.1mg)农药及相关化学品各标准物分别于10mL容量瓶中,根据标准物的溶解度选甲醇、甲苯、丙酮、乙腈或异辛烷溶解并定容至刻度(溶剂选择参见附录A),标准溶GB23200.13—20162液避光4℃保存,保存期为一年。4.4.2混合标准溶液(混合标准溶液A、B、C、D、E、F和G)按照农药及相关化学品的保留时间,将448种农药及相关化学品分成A、B、C、D、E、F和G七个组,并根据每种农药及相关化学品在仪器上的响应灵敏度,确定其在混合标准溶液中的浓度。本标准对448种农药及相关化学品的分组及其混合标准溶液浓度参见附录A。依据每种农药及相关化学品的分组、混合标准溶液浓度及其标准储备液的浓度,移取一定量的单个农药及相关化学品标准储备溶液于100mL容量瓶中,用甲醇定容至刻度。混合标准溶液避光4℃保存,保存期为一个月。4.4.3基质混合标准工作溶液农药及相关化学品基质混合标准工作溶液是用样品空白溶液配成不同浓度的基质混合标准工作溶液A、B、C、D、E、F和G,用于做标准工作曲线。基质混合标准工作溶液应现用现配。4.5材料4.5.1微孔过滤膜(尼龙):13mm×0.2μm。4.5.2CleanertTPT1)固相萃取柱:10mL,2.0g,或相当者。5仪器和设备5.1液相色谱-串联质谱仪:配有电喷雾离子源。5.2分析天平:感量0.1mg和0.01g。5.3鸡心瓶:200mL。5.4移液器:1mL。5.5样品瓶:2mL,带聚四氟乙烯旋盖。5.6具塞离心管:50mL。5.7氮气吹干仪。5.8低速离心机:4200r/min。5.9旋转蒸发仪。5.10高速组织捣碎机。6试样制备将茶叶样品放入粉碎机中粉碎,样品全部过425μm的标准网筛。混匀,制备好的试样均分成两份,装入洁净的盛样容器内,密封并标明标记。将试样于-18℃冷冻保存。7分析步骤7.1提取称取10g试样(精确至0.01g)于50mL具塞离心管中,加入30mL乙腈溶液,在高速组织捣碎机上以15000r/min匀浆提取1min,4200r/min离心5min,上清液移入鸡心瓶中。残渣加30mL乙腈,匀浆1min,4200r/min离心5min,上清液并入鸡心瓶中,残渣再加20mL乙腈,重复提取一次,上清液并入鸡心瓶中,45℃水浴,旋转浓缩至近干,氮吹至干,加入5mL乙腈溶解残余物,取其中1mL待净化。7.2净化在Cleanet-TPT柱中加入约2cm高无水硫酸钠,并将柱子放入下接鸡心瓶的固定架上。加样前先用5mL乙腈-甲苯溶液预洗柱,当液面到达硫酸钠的顶部时,迅速将样品提取液转移至净化柱上,并更换新鸡心瓶接收。在CleanertTPT柱上加上50mL贮液器,用25mL乙腈-甲苯溶液洗脱农药及相关化学品,合并于鸡心瓶中,并在45℃水浴中旋转浓缩至约0.5mL,于35℃下氮气吹干,1mL乙腈-水溶液溶解残渣,经0.2μm微孔滤膜过滤后,供液相色谱-串联质谱测定。CleanertTPT柱是Agela公司产品的商品名称,给出这一信息是为了方便本标准的使用者,并不是表示对该产品的认可。如果其他等效产品具有相同的效果,则可使用这些等效产品。GB23200.13—201637.3测定7.3.1液相色谱-串联质谱参考条件7.3.1.1A、B、C、D、E、F组农药及相关化学品LC-MS-MS测定条件a)色谱柱:ZORBAXSB-C18,3.5μm,100mm×2.1mm(内径)或相当者;b)流动相及梯度洗脱条件见表1;表1流动相及梯度洗脱条件步骤总时间/min流速/(μL/min)流动相A(0.1%甲酸水)/%流动相B(乙腈)/%00.0040099.01.013.0040070.030.026.0040060.040.039.0040060.040.0415.0040040.060.0519.004001.099.0623.004001.099.0723.0140099.01.0c)柱温:40℃;d)进样量:10μL;e)电离源模式:电喷雾离子化;f)电离源极性:正模式;g)雾化气:氮气;h)雾化气压力:0.28MPa;i)离子喷雾电压:4000V;j)干燥气温度:350℃;k)干燥气流速:10L/min;l)监测离子对、碰撞气能量和源内碎裂电压参见附录B。7.3.1.2G组农药及相关化学品LC-MS-MS测定条件a)色谱柱:ZORBAXSB-C18,3.5μm,100mm×2.1mm(内径)或相当者;b)流动相及梯度洗脱条件见表2;表2流动相及梯度洗脱条件步骤总时间/min流速/(μL/min)流动相A(5mmol/L乙酸铵水)/%流动相B(乙腈)/%00.0040099.01.013.0040070.030.026.0040060.040.039.0040060.040.0415.0040040.060.0519.004001.099.0623.004001.099.0723.0140099.01.0c)柱温:40℃;d)进样量:10μL;e)电离源模式:电喷雾离子化;f)电离源极性:负模式;g)雾化气:氮气;h)雾化气压力:0.28MPa;i)离子喷雾电压:4000V;j)干燥气温度:350℃;k)干燥气流速:10L/min;GB23200.13—20164l)监测离子对、碰撞气能量和源内碎裂电压参见附录B。7.3.2定性测定在相同实验条件下进行样品测定时,如果检出的色谱峰的保留时间与标准样品相一致,并且在扣除背景后的样品质谱图中,所选择的离子均出现,而且所选择的离子丰度比与标准样品的离子丰度比相一致(相对丰度>50%,允许±20%偏差;相对丰度>20%至50%,允许±25%偏差;相对丰度>10%至20%,允许±30%偏差;相对丰度≤10%,允许±50%偏差),则可判断样品中存在这种农药或相关化学品。7.3.3定量测定本标准中液相色谱-串联质谱采用外标-校准曲线法定量测定。为减少基质对定量测定的影响,定量用标准溶液应采用基质混合标准工作溶液绘制标准曲线。并且保证所测样品中农药及相关化学品的响应值均在仪器的线性范围内。448种农药及相关化学品多反应监测(MRM)色谱图参见附录C。7.4平行试验按以上步骤对同一试样进行平行试验。7.5空白试验除不称取试样外,均按上述步骤进行。8结果计算和表述液相色谱-串联质谱测定采用标准曲线法定量,标准曲线法定量结果按式(1)计算:Xi=ci×V×1000„„„„„„„„„„(1)m1000式中:Xi——试样中被测组分残留量,单位为毫克每千克(mg/kg);ci——从标准曲线上得到的被测组分溶液浓度,单位为微克每毫升(μg/mL);V——样品溶液定容体积,单位为毫升(mL);m——样品溶液所代表试样的重量,单位为克(g)。计算结果应扣除空白值,测定结果用平行测定的算术平均值表示,保留两位有效数字。9精密度9.1在重复性条件下获得的两次独立测定结果的绝对差值与其算术平均值的比值(百分率),
本文标题:GB 23200.13-2016 茶叶中448种农药及相关化学品残留量的测定 液相色谱-质谱法
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