分散固相萃取结合UPLC-Orbitrap MS联用测定鸡蛋中五氯苯酚残留量

建立了超高效液相色谱-静电轨道阱质谱联用测定禽蛋中五氯苯酚残留量的分析方法。取均质后的禽蛋样品经乙腈溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,高速离心分层后,取适量乙腈层溶液经0.1%(V∶V)甲酸稀释后,用酸性氧化铝粉末进行样品净化并以10000 r/min离心取上清液,过0.22μm滤膜后上机测定。使用反相色谱柱进行分离,流动相为乙腈:0.1%甲酸=75∶25,采用等度程序进行洗脱,静电轨道阱质谱进行定性定量分析。结果表明,五氯苯酚在0.5~100μg/kg范围内线性关系良好(r>0.995),方法的最低检出限为0.2μg/kg,最低定量限为0.5μg/kg,添加回收率在74.43%~96.85%之间,批内批间变异系数CV%<10%。该方法具有较好的准确度与精密度,适用于禽蛋中五氯苯酚残留量的测定。     

超高效液相色谱-静电轨道阱质谱正负切换同时筛查定量饲料中的51种农药残留化合物

建立了超高效液相色谱-静电轨道阱质谱法检测饲料中的51种农药残留物的检测方法和目标化合物的质谱数据库。饲料样品经0.1 mol/mL HCl : 甲醇=1:3提取,高速离心,经稀释后进样分析。采用Thermo Syncronis C18色谱柱(150 mm×2.1 mm, 3 μm)作为固定相,0.1 %甲酸和0.1%甲酸乙腈作为流动相进行梯度洗脱。质谱采用正负切换离子扫描,一对母离子和子离子的精确质量数进行定性,以母离子的响应强度积分面积进行定量分析。51种农药残留化合物在最优化条件下分离良好,在定量范围内均线性良好(线性相关系数r≥0.99),回收率也可达到50.61 ％～ 109.49 % ,相对标准偏差(RSD)小于9.1 %。本方法具有简便、快速、灵敏、准确等特点,适用于饲料中同时筛查和定量农药残留化合物。     

Confirmation of Pinnatoxins and Spirolides in Shellfish and Passive Samplers from Catalonia (Spain) by Liquid Chromatography Coupled with Triple Quadrupole and High-Resolution Hybrid Tandem Mass Spectrometry

Cyclic imines are lipophilic marine toxins that bioaccumulate in seafood. Their structure comprises a cyclic-imino moiety, responsible for acute neurotoxicity in mice. Cyclic imines have not been linked yet to human poisonings and are not regulated in Europe, although the European Food Safety Authority requires more data to perform a conclusive risk assessment for consumers. This work presents the first detection of pinnatoxin G (PnTX-G) in Spain and 13-desmethyl spirolide C (SPX-1) in shellfish from Catalonia (Spain, NW Mediterranean Sea). Cyclic imines were found at low concentrations (2 to 60 µg/kg) in 13 samples of mussels and oysters (22 samples analyzed). Pinnatoxin G has been also detected in 17 seawater samples (out of 34) using solid phase adsorption toxin tracking devices (0.3 to 0.9 µg/kg-resin). Pinnatoxin G and SPX-1 were confirmed with both low and high resolution (<2 ppm) mass spectrometry by comparison of the response with that from reference standards. For other analogs without reference standards, we applied a strategy combining low resolution MS with a triple quadrupole mass analyzer for a fast and reliable screening, and high resolution MS LTQ Orbitrap^® for unambiguous confirmation. The advantages and limitations of using high resolution MS without reference standards were discussed.     

液相色谱-四极杆-静电场轨道阱高分辨质谱法测定牛奶中8种氨基糖苷类抗生素残留

建立了一种测定牛奶中链霉素、双氢链霉素、庆大霉素、大观霉素、新霉素、卡那霉素、阿米卡星和安普霉素8种氨基糖苷类药物的液相色谱-四极杆-静电场轨道阱高分辨质谱方法。样品经提取和分子印迹固相萃取柱净化,新型“液态分离池”Obelisc R色谱柱分离,1%甲酸水溶液与1%甲酸乙腈溶液作为流动相梯度洗脱,四极杆/静电场轨道阱高分辨质谱准确定性并定量。8种待测组分均获得足够的色谱保留和分离,在各自浓度范围内呈现良好的线性关系,相关系数(R²)均大于0.99,定量限在0.5~20 μg/kg之间,平均回收率在68.0%~104.6%之间,批内与批间RSD均不高于11.3%。该法区别于传统方法：不添加离子对试剂,不使用含缓冲盐流动相,最大限度减少了对质谱检测器的污染;采用高分辨质谱检测器定性定量,结果准确可靠;灵敏度较现行国标显著提高。该方法具有良好的可操作性和重现性,适用于牛奶中氨基糖苷类药物的快速筛查、定性筛选和定量测定。     

超高效液相色谱-二极管阵列-四极杆静电轨道阱质谱法对杆菌肽组分的分析

开发建立了超高效液相色谱-二极管阵列-串联四级杆静电场轨道阱高分辨质谱联用分析杆菌肽组分的方法。采用(Phenomenex C₁₈100 mm×3.0 mm,2.6μm)色谱柱,以0.1%甲酸溶液-0.1%甲酸甲醇乙腈(75+25)溶液为流动相,0.3 mL/min线性梯度洗脱分离,紫外吸收波长为254 nm。采集杆菌肽各组分质谱母离子及其对应子离子,并进行解析,推测组分的结构。在所建立的条件下,检测出9个组分,杆菌肽各组分之间分离良好。利用紫外与质谱归一化法测定含量,两种结果相对偏差在0.01%~3.53%之间。建立的超高效液相色谱-二极管阵列-串联四级杆静电场轨道阱高分辨质谱法能有效分析多肽类药物杆菌肽各组成成分,为杆菌肽的质量控制和工艺优化提供了参考。     

超高效液相色谱-静电场轨道阱高分辨质谱法测定茶叶中21种农药残留量

采用超高效液相色谱-静电场轨道阱高分辨质谱,建立了茶叶中21种农药残留量的检测方法。茶叶样品经甲醇和水（V_甲醇∶V_水=1∶1）提取后,采用乙二胺-N-丙基硅烷和强阳离子交换剂作为混合吸附剂进行萃取净化。以C₁₈色谱柱进行色谱分离,采用Full Scan扫描模式进行定性、定量分析。结果显示,21种农药在0.5~200βμg·L^-1范围内均呈良好的线性关系,相关系数（r²）大于0.99。在10、50、100βμg·kg^-1 3个加标水平下,平均回收率为70%~125%之间,相对标准偏差（RSD）小于15%,定量限为10βμg·kg^-1。本方法操作简单快速,灵敏度高,适用于茶叶中21种农药残留检测。