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1 第 10 卷第 12 期食品安全质量检测学报 Vol. 10 No 年 6 月 Journal of Food Safety and Quality Jun., 2019 QuEChERS- - 黄松 1, 宋安华 1, 陈穗 2, 刘佳 1, 王成龙 1, 刘占 2, 赵金利 1, 陈彦宏黄小清 1 1,2*, 王宇 1, (1. 广州市食品检验所, 广州 ; 2. 广东美味鲜调味食品有限公司, 中山 ) 摘要 : 目的建立一种 QuEChERS- 气相色谱 - 串联质谱法 (gas chromatography-tandem mass spectrometry, GC-MS/MS) 测定油麦菜中 64 种农药多残留基质效应的分析方法方法样品经乙腈提取, N- 丙基乙二胺 (PSA) 净化, 配制基质标准点与溶剂标准点进行峰面积对比来评价基质效应结果油麦菜基质对 18.8% 的农药多残留项目不表现基质效应, 对 37.5% 的项目有强基质效应 ; 当基质液稀释至 50 倍后, 对 81.3% 的农药多残留项目不表现出基质效应 ; 稀释至 100 倍后, 有氟胺氰菊酯氯氟氰菊酯和水胺硫磷 3 种处于中等基质效应结论在使用气相色谱 - 串联质谱法测定油麦菜中农药多残留含量的过程中, 需要通过稀释来准确定量时, 要注化合物在不同稀释比例的基质下所受到的基质效应的影响该方法快速简单, 适用于蔬菜水果中农药多残留基质效应的测定和评估关键词 : QuEChERS; 气相色谱串联质谱 ; 基质效应 ; 农药多残留 Determination of matrix effects of pesticide multi-residues in lettuces by QuEChERS-gas chromatography-tandem mass spectrometry HUANG Song 1, SONG An-Hua 1, CHEN Sui 2, LIU Jia 1, WANG Cheng-Long 1, LIU Zhan 2, ZHAO Jin-Li 1, CHEN Yan-Hong 1, HUANG Xiao-Qing 1, WANG Yu 1,2* (1. Guangzhou Institute for Food Inspection, Guangzhou , China; 2. Guangdong Meiweixian Flavoring Foods Co. Ltd, Zhongshan , China) ABSTRACT: Objective To establish a method for the determination of matrix effects of 64 pesticides multi-residue in lettuce by QuEChERS-gas chromatography-tandem mass spectrometry (GC-MS/MS). Methods Samples were extracted with acetonitrile, and purified by primary secondary amine (PSA). The matrix effects were evaluated by comparing the peak areas of the matrix standard and the solvent standard. Results The lettuce substrate did not exhibit a matrix effect on 18.8% of pesticide multi-residue projects, and had a strong matrix effect on 37.5% of the projects. When the substrate solution was diluted to 50 times, it did not exhibit a matrix effect on the 81.3% pesticide multi-residue projects. And the tau-fluvalinate, cyhalothrin and isocarbophos still showed a moderate matrix effect even when the matrix solution was diluted with 100 times. Conclusion In the process of determining 基金项目 : 广州市科技计划项目 ( ) 广东美味鲜博士后创新基地科研项目(2018) Fund: Supported by the Science and Technology Project of Guangzhou ( ), and Post-doctoral Innovation Base Project of Meiweixian Guangdong (2018) * 通讯作者 : 王宇, 博士, 高级工程师, 主要研究方向为食品安全检测 @qq.com *Corresponding author: WANG Yu, Ph.D, Senior Engineer, Guangzhou Institute for Food Inspection, Guangzhou, , China, @qq.com

2 3864 食品安全质量检测学报第 10 卷 the multi-residue content of pesticides in lettuce by gas chromatography-tandem mass spectrometry, it is necessary to accurately quantify by dilution, and to influence the matrix effect of the compound under different dilution ratios. This method is rapid and simple, which is suitable for determination and evaluation the matrix effects in vegetables and fruits. KEY WORDS: QuEChERS; gas chromatography-tandem mass spectrometry; matrix effects; pesticides multi-residue 1 引言 QuEChERS 法是基于分散固相萃取技术发展起来的一种集萃取和净化为一体的新型前处理方法, 该法经济环保且快速高效, 适合各种样品基质及多种农药残留项目的检测, 已成为多农残分析的首选方法但同时, 由于 QuEChERS 法是采用了分散固相萃取的方法进行净化, 与传统方法相比, 势必会引入更多的基质, 造成基质效应, 从而影响检测结果的准确性按照美国临床实验室标准化委员会的定义, 基质效应是指样品中除目标分析物之外的其他成分对待测物测定值的影响, 即基质对分析方法准确测定分析物能力的干扰 [1] 根据基质对检测信号响应值的不同影响, 基质效应可分为基质增强和减弱效应在气相色谱 - 串联质谱 (gas chromatographytandem mass spectrometry, GC-MS/MS) 中, 基质的存在减少了色谱系统活性位点与待测物作用的机会, 让更多的待测物进入色谱柱, 使得待测物检测信号增强 [2 4] 近年来, 消除和补偿基质效应的方法主要有基质净化法 [5 7] 基质匹配校准法 [8 10] 分析物保护剂法 [11 13] [14 16] 同位素标记法等, 基质匹配校准法不仅要求配制标准曲线所用的基质与样品基质一致, 而且这 2 种基质液的浓度也应保持一致油麦菜是一种四季可播种的蔬菜, 叶绿素含量高, 经过 QuEChERS 处理后仍具有明显的基质效应 ; 且在日常监督抽检中, 多次出现油麦菜中毒死蜱氧乐果氟氯氰菊酯超标且检出浓度较高的情况, 而这些农药的限量值大多较低 (0.02~0.2 mg/kg) [17], 因此, 如何补偿基质效应准确定量, 对阳性样品的判定非常重要本研究采用基质匹配校准法, 以 QuEChERS 处理后的空白油麦菜为基质溶液配制标准溶液, GC-MS/MS 检测, 研究在不同基质浓度下农药化合物的基质效应, 从而为实际检测中阳性样品稀释后的准确定量提供科学的指导依据 2 材料与方法 2.1 仪器与试剂 TRACE 1300-TSQ 8000 Evo 气相色谱三重四极杆串联质谱 ( 美国 Thermo Scientific 公司 ), 配电子轰击离子源 (EI); TR-PESTICIDE II 气相色谱柱 (30 m 0.25 mm, 0.25 μm, 美国 Thermo Fisher Scientific 公司 ); Allegra X-30R Centrifuge 高速离心机 ( 美国 BECKMAN 公司 ); MS3 涡旋振荡器 KS501 数显型圆周振荡器 ( 德国 IKA 公司 ); ME2002E 电子天平 ( 瑞士 METTLER TOLEDO 公司 ) 53 种有机磷 26 种有机氯和菊酯 (100 mg/l, 美国 O2Si 公司 ); 乙腈正己烷丙酮 ( 色谱纯, 美国 Fisher Chemical 公司 ); QuEChERS 分散固相萃取盐包 (4 g MgSO 4 1 g NaCl 1 g 柠檬酸钠 0.5 g 三水合二柠檬酸二钠 ) QuEChERS 分散固相萃取净化管 (15 ml, 150 mg PSA, 900 mg MgSO 4 ) 陶瓷均质子( 美国 Agilent 公司 ) 油麦菜购于市场, 经筛查为阴性样品 2.2 实验方法标准溶液的配制准确吸取 1 ml 2 种混合标准溶液于 10 ml 容量瓶中, 用正己烷 : 丙酮 (1:1, V:V) 定容, 得到浓度为 10 mg/l 的混合标准储备溶液, 18 下存储备用, 有效期为 3 个月提取准确称取 g ( 精确到 0.01 g) 样品于 50 ml 离心管中, 加入 20 ml 乙腈, 振荡 30 min 后置于冰箱冷冻 20 min 每只离心管加入 1 个陶瓷均质子, 1 袋萃取盐包, 快速振摇 15 min, 使盐均匀分散, 8000 r/min 冷冻离心 3 min, 取上层清液, 待净化净化取 5 ml 上清液于净化管中, 剧烈振摇 15 min, 8000 r/min 离心 3 min, 取上清液过膜备用标准点的配制将上述净化后的基质用乙腈分别稀释至倍, 得到 4 种不同稀释体积的基质溶液 ; 以基质溶液为溶剂, 配制得到 100 ng/ml 的 4 个稀释体积下的浓度点, 每个稀释体积平行配制 3 组用乙腈为溶剂, 配制得到 100 ng/ml 的溶剂浓度点, 平行配制 3 组仪器条件气相色谱条件 : 进样口温度 270, 进样量 1 μl, 不分流进样 ; 载气为氦气 (99.999%), 恒定流量 1.2 ml/min; 程序升温 : 初温 40, 保持 1.5 min, 以 25 /min 升温至 90, 保持 1.5 min, 然后以 25 /min 升至 180, 再以 5 /min 升至 280, 再 10 /min 升至 300, 保持 5 min; 传输线温度 : 300 质谱条件 : EI(electron impact) 离子源温度 : 300 ; 发

3 第 12 期黄松, 等 : QuEChERS- 气相色谱 - 串联质谱法测定油麦菜中农药多残留的基质效应 3865 射电流 : 25 μa; 碰撞气 : 氩气 (99.999%) 基质效应的评价基质效应 (matrix effect, ME): A ME 1 100% B 其中 : A 表示基质标准点的峰面积, B 溶剂标准点的峰面积 [18,19], 当 ME>0 时, 表示基质对待测物有基质增强效应 ; ME<0 为基质抑制效应 ME 20%, 可认为该基质没有基质效应 ; 若其值在 20%~50% 之间, 则表明该基质有中等基质效应 ; 若 ME >50%, 则表明基质效应很强 [13,20] 3 结果与讨论 3.1 基质效应的范围油麦菜的提取液的颜色较深, 基质成分比较复杂, 可能存在比较严重的基质效应对比基质与溶剂标准点, 计算 ME 值得到结果如表 1 所示 Table 1 表 1 不同稀释浓度基质液的基质效应 (ME 值 )(n=3) Matrix effect (ME) of matrix solution in different dilution concentrations (n=3) 编号项目不稀释 /% 稀释 10 倍 /% 稀释 20 倍 /% 稀释 50 倍 /% 稀释 100 倍 /% 1 艾氏剂 4.3± ± ± ± ±0.6 2 益棉磷 85.1± ± ± ± ±1.0 3 α ± ± ± ± ±0.3 4 β ± ± ± ± ±1.4 5 δ ± ± ± ± ±2.4 6 γ ± ± ± ± ±2.1 7 联苯菊酯 103.2± ± ± ± ±3.1 8 乙基溴硫磷 50.1± ± ± ± ±1.7 9 溴硫磷 20.7± ± ± ± ± 硫线磷 36.1± ± ± ± ± 氯丹 32.0± ± ± ± ± 毒死蜱 14.8± ± ± ± ± 甲基毒死蜱 26.8± ± ± ± ± 蝇毒磷 127.1± ± ± ± ± 氟氯氰菊酯 37.3± ± ± ± ± 氯氟氰菊酯 102.8± ± ± ± ± 氯氰菊酯 58.8± ± ± ± ± p,p-ddd 38.6± ± ± ± ± p,p-dde 24.3± ± ± ± ± p,p-ddt 44.8± ± ± ± ± o,p-ddt 14.3± ± ± ± ± 溴氰菊酯 149.9± ± ± ± ± 除线磷 31.5± ± ± ± ± 敌敌畏 22.5± ± ± ± ± 狄氏剂 18.3± ± ± ± ± 乐果 44.1± ± ± ± ± 乙拌磷 18.5± ± ± ± ± 硫丹 18.8± ± ± ± ±0.8

4 3866 食品安全质量检测学报第 10 卷续表 1 编号项目不稀释 /% 稀释 10 倍 /% 稀释 20 倍 /% 稀释 50 倍 /% 稀释 100 倍 /% 29 异狄氏剂 25.2± ± ± ± ± 苯硫磷 87.9± ± ± ± ± 灭线磷 46.8± ± ± ± ± 伐灭磷 88.4± ± ± ± ± 苯线磷 96.7± ± ± ± ± 皮蝇磷 58.7± ± ± ± ± 杀螟硫磷 31.4± ± ± ± ± 甲氰菊酯 97.6± ± ± ± ± 倍硫磷 24.3± ± ± ± ± 氰戊菊酯 152.4± ± ± ± ± 氟氰戊菊酯 88.3± ± ± ± ± 氟胺氰菊酯 728.9± ± ± ± ± 地虫硫磷 20.4± ± ± ± ± 七氯 7.8± ± ± ± ± 水胺硫磷 144.7± ± ± ± ± 异柳磷 25.8± ± ± ± ± 甲基异柳磷 29.7± ± ± ± ± 马拉硫磷 64.7± ± ± ± ± 杀扑磷 65.0± ± ± ± ± 灭蚁灵 21.0± ± ± ± ± 甲基对硫磷 49.0± ± ± ± ± 甲拌磷 34.6± ± ± ± ± 伏杀硫磷 109.2± ± ± ± ± 硫环磷 52.8± ± ± ± ± 亚胺硫磷 103.4± ± ± ± ± 磷胺 87.4± ± ± ± ± 乙基嘧啶磷 25.8± ± ± ± ± 甲基嘧啶磷 29.3± ± ± ± ± 丙溴磷 100.2± ± ± ± ± 胺丙畏 40.6± ± ± ± ± 喹硫磷 25.2± ± ± ± ± 治螟磷 26.9± ± ± ± ± 特丁硫磷 31.1± ± ± ± ± 杀虫畏 109.6± ± ± ± ± 三唑磷 101.3± ± ± ± ± 毒壤磷 19.1± ± ± ± ±0.8

5 第 12 期黄松, 等 : QuEChERS- 气相色谱 - 串联质谱法测定油麦菜中农药多残留的基质效应 3867 由实验结果可知, 当基质液不稀释时, 所有的 ME 的值都是正值 ( 如表 1 所示 ), 说明油麦菜基质对 64 种农药残留的基质效应都是基质增强效应 ; 其中 ME 小于 20% 的项目有 12 种 : 艾氏剂 α-666 β-666 δ-666 γ-666 毒死蜱 o,p-ddt 狄氏剂乙拌磷硫丹七氯毒壤磷; 有 24 种均为 ME 大于 50%, 即油麦菜基质对 37.5% 的项目表现为强基质效应 ME 大于 100% 的项目有 12 个 ( 联苯菊酯蝇毒磷氯氟氰菊酯溴氰菊酯氰戊菊酯氟胺氰菊酯水胺硫磷伏杀硫磷亚胺硫磷丙溴磷杀虫畏三唑磷 ), 有机氯中基质效应较为严重的均为拟除虫菊酯类农药, 其中氟胺氰菊酯的 ME 值高达 728%, 表明其具有极强的基质效应有机磷中基质效应较为严重的大多带有 P=O 或 P=S 等基团, 该结果与文献中观察到的现象保持一致 [3,21] 将基质液用溶剂稀释时, 稀释的倍数越大, 则基质效应越微弱, 如液相色谱质谱联用法常采用稀释的方法来减弱基质效应的影响 [22] 如图 1 所示, 实验结果表明稀释倍数为倍的时候, 基质效应的减少程度有限, 稀释至 50 倍时, 油麦菜基质对 81.3% 的项目不表现出基质效应, 当稀释倍数为 100 倍时, 仍对氟胺氰菊酯氯氟氰菊酯和水胺硫磷有中等基质效应但当稀释倍数大于 50 倍时, 有些项目开始表现出基质减弱效应这可能是由于过多的杂质吸附在衬管上之后, 这些杂质形成新的吸附位点, 使高倍数稀释的待测物的浓度降低图 3 所示是甲基异柳磷和七氯在不同稀释比例基质液的基质效应情况甲基异柳磷在基质液稀释 20 倍以内的时候, 基质效应变化不大, 表现出中等基质效应 ; 当稀释倍数为 20 到 50 倍时, 其基质效应有较大程度的降低 ; 超过 50 倍之后, 基质效应变化很小, 不表现出基质效应因此, 当对样品的稀释倍数超过 50 倍数时, 可采用溶剂标准曲线定量七氯在不同比例的稀释过程中均未表现出基质效应, 说明油麦菜基质对其影响很小, 在定量过程中可以使用溶剂标准曲线定量图 2 氟胺氰菊酯在不同稀释比例的油麦菜基质中的基质效应 Fig.2 Matrix effects of fluvalinate in lettuce with different dilutions 图 1 64 种农药残留在不同稀释比例的油麦菜基质中的基质效应 Fig.1 Matrix effects of 64 pesticides residue in lettuce with different dilutions 3.2 不同浓度基质液对基质效应的影响图 3 Fig.3 甲基异柳磷和七氯在不同稀释比例的油麦菜基质中的基质效应 Matrix effects of isofenphos-methyl and heptachlor in lettuce with different dilutions 在所有检测的项目中, 氟胺氰菊酯的基质效应最为强烈, 不同稀释倍数的基质效应的差别很大, 随着基质稀释倍数的增加, 基质效应虽有降低, 但当稀释 100 倍时仍受到中等基质效应影响, 如图 2 示因此, 若阳性超标样品进行 10 倍稀释后, 依然使用未稀释的基质标准曲线来对其进行定量的时候, 会对结果产生很大影响, 若是稀释 100 倍后, 则定量结果偏差会更大 4 结论本研究通过比较溶剂标准点不同稀释倍数的基质标准点的峰面积, 可以得到, 当使用 GC-MS/MS 测定农药多残留时, 农药化合物受油麦菜基质效应的影响各异实验表明, 艾氏剂 α-666 β-666 δ-666 γ-666 毒死蜱 ο,p-ddt 狄氏剂乙拌磷硫丹七氯毒壤磷受基质

3868 食品安全质量检测学报第 10 卷干扰较小, 可采用溶剂标准实验结果进行准确定量 ; 联苯菊酯蝇毒磷氯氟氰菊酯溴氰菊酯氰戊菊酯氟胺氰菊酯水胺硫磷伏杀硫磷亚胺硫磷丙溴磷杀虫畏三唑磷等受基质干扰严重, 当出现高浓度阳性样需要稀释后再定量的过程中, 必须要对配制标准曲线所用的基质液进行等比例的稀释, 才能保证实验结果的准确性因此,

Explanation of the matrix-induced chromatographic response enhancement of organophosphorus pesticides during open tubular column gas chromatography with splitless or hot on-column injection and flame

6 3868 食品安全质量检测学报第 10 卷干扰较小, 可采用溶剂标准实验结果进行准确定量 ; 联苯菊酯蝇毒磷氯氟氰菊酯溴氰菊酯氰戊菊酯氟胺氰菊酯水胺硫磷伏杀硫磷亚胺硫磷丙溴磷杀虫畏三唑磷等受基质干扰严重, 当出现高浓度阳性样需要稀释后再定量的过程中, 必须要对配制标准曲线所用的基质液进行等比例的稀释, 才能保证实验结果的准确性因此, 采用基质匹配法对基质效应进行校准的过程中, 由于不同项目在基质液稀释后受到基质效应的影响不同, 基质匹配不仅包括基质类型的一致或相同, 还应包括基质液与标准曲线的稀释比例, 即基质浓度相匹配参考文献 [1] Erney DR, Gillespie AM, Gilvydis DM, et al. Explanation of the matrix-induced chromatographic response enhancement of organophosphorus pesticides during open tubular column gas chromatography with splitless or hot on-column injection and flame photometric detection [J]. J Chromatogr A, 1993, 638(1): [2] Rimayi C, Odusanya D, Mtunzi F, et al. Alternative calibration techniques for counteracting the matrix effects in GCMS-SPE pesticide residue analysis-astatistical approach [J]. Chemosphere, 2015, 118: [3] Sanchez-Brunete C, Albero B, Martin G, et al. Determination of pesticide residues by GC-MS using analyte protectants to counteract the matrix effect [J]. Jap Soc Anal Chem, 2005, 21(11): [4] Rahman MM, Choi JH, El-Aty AMA, et al. Pepper leaf matrix as a promising analyte protectant prior to the analysis of thermolabile terbufos and its metabolites in pepper using GC-FPD [J]. Food Chem, 2012, 133(2): [5] Tuzimski T, Rejczak T. Application of HPLC-DAD after SPE/QuEChERS with ZrO 2 -based sorbent in D-SPE clean-up step for pesticide analysis in edible oils [J]. Food Chem, 2016, 190: [6] Bedassa T, Gure A, Megersa N, et al. Modified QuEChERS method for the determination of multi class pesticide residues in fruit samples utilizing high-performance liquid chromatography [J]. Food Anal Methods, 2015, 8(8): [7] Kemmerich M, Rizzetti TM, Martins ML, et al. Optimization by central composite design of a modified QuEChERS method for extraction of pesticide multiresidue in sweet pepper and analysis by ultra-high performance liquid chromatography-tandem mass spectrometry [J]. Food Anal Methods, 2015, 8(3): [8] Fernandes VC, Freitas M, Pacheco JPG, et al. Magnetic dispersive micro solid-phase extraction and gas chromatography determination of organophosphorus pesticides in strawberries [J]. J Chromatogr A, 2018, 1566: [9] Martins ML, Kemmerich M, Prestes OD, et al. Evaluation of an alternative fluorinated sorbent for dispersive solid-phase extraction clean-up of the quick, easy, cheap, effective, rugged, and safe method for pesticide residues analysis [J]. J Chromatogr A, 2017, 1514: [10] Qin YH, Zhang JR, Li YF, et al. Automated multi-filtration cleanup with nitrogen-enriched activated carbon material as pesticide multi-residue analysis method in representative crop commodities [J]. J Chromatogr A, 2017, 1515: [11] Bresin B, Piol M, Fabbro D, et al. Analysis of organo-chlorine pesticides residue in raw coffee with amodified "quick easy cheap effective rugged and safe" extraction/clean up procedure for reducing the impact of caffeine on the gas chromatography-mass spectrometry measurement [J]. J Chromatogr A, 2015, 1376: [12] Sapozhnikova Y. High-throughput analytical method for 265 pesticides and environmental contaminants in meats and poultry by fast low pressure gas chromatography and ultra-high performance liquid chromatography tandem mass spectrometry [J]. J Chromatogr A, 2018, 1572: [13] Mastovska K, Lehotay SJ, Anastassiades M. Combination of analyte protectants to overcome matrix effects in routine GC analysis of pesticide residues in food matrixes [J]. Anal Chem, 2005, 77(24): [14] Parrilla VP, Hakme E, Ucles S, et al. Large multiresidue analysis of pesticides in edible vegetable oils by using efficient solid-phase extraction sorbents based on quick, easy, cheap, effective, rugged and safe methodology followed by gas chromatography-tandem mass spectrometry [J]. J Chromatogr A, 2016, 1463: [15] Trevisan MTS, Owen RW, Calatayud-Vernich P, et al. Pesticide analysis in coffee leaves using a quick, easy, cheap, effective, rugged and safe approach and liquid chromatography tandem mass spectrometry: Optimization of the clean-up step [J]. J Chromatogr A, 2017, 1512: [16] Wang JS, He ZY, Wang L, et al. Automatic single-step quick, easy, cheap, effective, rugged and safe sample preparation devices for analysis of pesticide residues in foods [J]. J Chromatogr A, 2017, 1521: [17] GB 食品安全国家标准食品中农药最大残留限量 [S]. GB National food safety standard-maximum residue limits of pesticides in food [S]. [18] Besil N, Cesio V, Heinzen H, et al. Matrix effects and interferences of different citrus fruit co-extractives in pesticide residue analysis using ultra-high-performance liquid chromatography-high-resolution mass spectrometry [J]. J Agric Food Chem, 2017, 65: [19] Arias JLDO, Rombaldi C, Caldas SS, et al. Alternative sorbents for the dispersive solid-phase extraction step in quick, easy, cheap, effective, rugged and safe method for extraction of pesticides from rice paddy soils with determination by liquid chromatography tandem mass spectrometry [J]. J Chromatogr A, 2014, 1360: [20] Ferrer C, Lozano A, Aguera A, et al. Overcoming matrix effects using the dilution approach in multiresidue methods for fruits and vegetables [J]. J Chromatogr A, 2011, 1218: [21] Poole CF. Matrix-induced response enhancement in pesticide residue analysis by gas chromatography [J]. J Chromatogr A, 2007, 1158: [22] Jiao WT, Xiao Y, Qian XS, et al. Optimized combination of dilution and refined QuEChERS to overcome matrix effects of six types of tea for determination eight neonicotinoid insecticides by ultra performance liquid chromatography-electrospray tandem mass spectrometry [J]. Food Chem, 2016, 210: 作者简介 ( 责任编辑 : 韩晓红 ) 黄松, 硕士, 助理工程师, 主要研究方向为食品安全检测 hsonging@163.com 王宇, 博士, 高级工程师, 主要研究方向为食品安全检测 @qq.com

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Microsoft Word _黄 松二校

Microsoft Word _黄松二校