液相色谱法检测水果蔬菜中的烟碱类农药残留

建立了果蔬样品中5种烟碱类农药(噻虫嗪、吡虫啉、啶虫脒、噻虫啉、噻虫胺)残留的液相色谱快速检测方法。样品采用乙腈提取,浓缩,水转溶后经ENVI-18固相萃取柱净化,0.02 mol/L NaOH预淋洗除去柱上中等极性干扰物,100%乙腈1 mL洗脱5种烟碱类残留,反相高效液相色谱-二极管阵列检测器检测。在黄瓜空白基质中0.1~1.0 mg/kg的加标浓度范围内,5种农药的回收率为50.8%~108.9%,相对标准偏差(RSD)小于15%;而苹果、梨、香蕉、西红柿和韭菜空白基质在0.1~1.0 mg/kg添加水平下,5种农药的回收率均大于80%,RSD小于11%。所测试的6种果蔬样品中噻虫嗪、噻虫胺、吡虫啉的检出限(LOD)为0.01~0.02 mg/kg,啶虫咪和噻虫啉的LOD为0.03~0.05 mg/kg,方法可满足水果蔬菜中烟碱类农药多残留分析的要求。     

在线固相萃取-超高效液相色谱/串联质谱法测定水中新烟碱类杀虫剂

采用在线固相萃取-超高效液相色谱/串联质谱技术建立了水中啶虫脒、噻虫胺、吡虫啉、噻虫啉、噻虫嗪、呋虫胺及烯啶虫胺7种新烟碱类杀虫剂的检测方法。样品滤膜过滤后,经HLB Dierect Connect HP在线固相萃取小柱富集纯化,以ACQUITY UPLC BEH C₁₈为分析柱串联质谱进行检测,外标法定量。在线富集水样中新烟碱类物质在5.0~200 ng/L范围内线性关系良好,相关系数R²均大于0.99;检出限为0.30~2.92 ng/L,相对标准偏差均小于10%。该法可用于保障水环境安全、及时提供污染信息。     

QuEChERS-高效液相色谱/串联质谱法同时测定蜂蜜中9种新烟碱类杀虫剂残留

建立了蜂蜜中吡呀酮、吡虫啉、啶虫脒、噻虫嗪、噻虫啉、烯啶虫胺、噻虫胺、呋虫胺和氯噻啉9种新烟碱类杀虫剂的QuEChERS-高效液相色谱/串联质谱(HPLC-MS/MS)检测方法。样品以水提取,采用N-丙基乙二胺(PSA)和酸性Al2O3净化,用Zorbax Eclipse Plus C18柱(100×3.0mm,1.8μm)分离,以乙腈-0.1%甲酸水溶液为流动相,梯度洗脱,采用电喷雾正离子模式(ESI+)、多重反应监测(MRM)检测目标分析物,基质匹配标准溶液外标法定量。结果表明:9种杀虫剂均具有良好的线性关系(r20.9969);方法检出限为0.3~0.8μg/kg;定量限为1.0~2.5μg/kg;在2.5、10、25μg/kg三个添加水平下,杂花蜜、油菜蜜、棉花蜜和葵花蜜四种基质样品中9种杀虫剂的平均回收率在81.7%~106.7%范围,相对标准偏差(RSDs)在4.2%~9.4%之间。该方法分析速度快、灵敏度高、重现性好,适用于蜂蜜中新烟碱类杀虫剂残留的快速检测和确证。     

盐析辅助均相液液萃取/分散固相萃取-超高效液相色谱串联质谱法测定蜂蜜中新烟碱类农药残留

以盐析辅助均相液液萃取结合分散固相萃取作为前处理方法,建立了超高效液相色谱串联质谱快速检测蜂蜜中吡虫啉、噻虫嗪、噻虫胺、噻虫啉、啶虫脒及氯噻啉6种新烟碱类农药残留的分析方法。样品用乙腈提取,氯化钠盐析分层,提取液经分散固相萃取法净化,采用超高效液相色谱串联质谱检测器进行分析。考察了萃取剂种类、体积及氯化钠质量对萃取效率的影响,评估了在优化实验条件下的基质效应和方法性能。结果表明:除吡虫啉外,其余5种新烟碱类农药的基质效应均大于10%。6种新烟碱类农药在0.2~100μg/L范围内线性关系良好,相关系数(r2)为0.998 1~0.999 7。加标浓度为1.0~50.0μg/kg时,6种新烟碱类农药的加标回收率为77.0%~106%,相对标准偏差为2.4%~19.8%。方法的检出限为0.2~0.4μg/kg,定量下限为1.0μg/kg。该方法前处理简单,分析时间短,准确度和灵敏度高,重现性好,适用于蜂蜜中6种新烟碱类农药微量残留的快速测定。     

分散固相萃取/液相色谱-串联质谱法测定花生及土壤中的噻虫啉

建立了一种检测土壤、花生植株、花生果实及花生壳中噻虫啉的分散固相萃取(DSPE)/液相色谱-串联质谱(HPLC-MS/MS)快速检测方法。对提取溶剂、不同分散固相吸附剂及其用量进行了考察和优化。样品经0.1%乙酸乙腈溶液提取后,以50 mg N-丙基乙二胺吸附剂(PSA)、50 mg十八烷基键合硅胶(C18)和10 mg石墨化碳黑(GCB)固相萃取填料净化,采用水-甲醇作为流动相进行梯度洗脱,电喷雾正离子(ESI+)模式电离,质谱采用多离子监测模式(MRM)进行定性分析,基质标准曲线外标法进行定量分析。在0.1~50μg/kg范围内,不同基质中噻虫啉的线性相关系数均大于0.996。在土壤、花生植株、花生果实及花生壳中添加3个不同浓度水平的噻虫啉标准品,得到噻虫啉的回收率为70.6%~119%,相对标准偏差不大于16.6%,方法的定量下限为1.0~5.0μg/kg,能够满足现有国际限量的要求。     

液相色谱-串联质谱法测定果蔬中4种新型卵菌纲杀菌剂残留

建立了蔬菜和水果中噻唑菌胺、苯噻菌胺、氟啶酰菌胺和双炔酰菌胺4种新型卵菌纲杀菌剂的分散固相萃取-液相色谱-串联质谱检测方法.样品经乙腈均质提取,混合使用乙二胺-N-丙基硅烷(PSA)和ODSC18-N两种基质分散净化剂净化,采用液相色谱-三重四级杆串联质谱(LC/MS/MS)检测.实验通过空白基质溶液稀释标准建立校正的...     

液相色谱-电喷雾电离三级四极杆质谱法测定茶叶中6种烟碱类农药残留

应用液相色谱-电喷雾电离三级四极杆质谱(LC-ESI-MS/MS)方法测定茶叶中呋虫胺、噻虫嗪、噻虫胺、吡虫啉、啶虫咪和噻虫啉烟碱类农药残留.前处理方法包括添加同位素内标吡虫啉-D4,乙腈提取,再用活性碳和Oasis(HLB)固相小柱净化.该方法采用正离子方式,多反应监测每种烟碱类杀虫剂各两对离子进行定性、定量分析.方法在0.01～0.4 mg/kg范围内具有良好的线性关系.实验了3个添加水平0.02、0.04和0.2 mg/kg,回收率范围为80.1%～106.1%;相对标准偏差小于9.7%;方法检出限(LOQ)均为0.02 mg/kg.本方法简便、快速、准确,各项技术指标满足国内外法规的要求,可用于茶叶样品中烟碱类农药残留的确证检测.     

QuEChERS-高效液相色谱-串联质谱法同时测定生活饮用水中11种新烟碱类杀虫剂的含量

提出了QuEChERS-高效液相色谱-串联质谱法(HPLC-MS/MS)同时测定生活饮用水中11种新烟碱类杀虫剂(吡虫啉、烯啶虫胺、啶虫脒、噻虫啉、氯噻啉、环氧虫啶、噻虫嗪、噻虫胺、呋虫胺、氟啶虫胺腈、氟啶虫酰胺)含量的方法。5 mL过滤后的水样用含1%(体积分数)甲酸的二氯甲烷溶液提取两次,合并下层提取液,氮吹至干,加入50 mg N-丙基乙二胺(PSA)和1 mL体积比65:35的0.2%(体积分数,下同)甲酸溶液-乙腈的混合溶液,涡旋后过0.22μm聚醚砜滤膜。以不同体积比的0.2%甲酸溶液-乙腈的混合溶液为流动相进行梯度洗脱,分离后的11种目标物经电喷雾离子源正离子模式扫描,以多反应监测模式检测,外标法定量。结果表明：11种新烟碱类杀虫剂的质量浓度在一定范围内与对应的峰面积呈线性关系,测定下限(10S/N)为0.02～0.08μg·L^-1;在3个加标浓度水平下,11种目标物的回收率为62.1%～101%,测定值的相对标准偏差(n=6)为5.0%～15%。方法用于8份自来水、4份河水和3份水库水样品分析,结果显示4份河水样品和2份水库水样品中检出新烟碱类杀虫...     

多壁碳纳米管分散固相萃取-液相色谱-串联质谱法测定茶叶中5种烟碱类农药的残留量

采用多壁碳纳米管分散固相萃取-液相色谱-串联质谱法测定茶叶中啶虫脒、噻虫胺、吡虫啉、噻虫啉、噻虫嗪等5种烟碱类农药的残留量。粉碎后的茶叶样品用水浸泡30min后,用乙腈提取,以多壁碳纳米管作为吸附剂去除杂质。以Agilent C18色谱柱为分离柱,以不同体积比的5mmol·L~(-1)乙酸铵-0.1%(体积分数)甲酸溶液和甲醇的混合液为流动相进行梯度洗脱,采用电喷雾正离子源和多反应监测模式检测。5种烟碱类农药的质量浓度均在1.0~20μg·L~(-1)内与其对应的峰面积呈线性关系,测定下限(10S/N)均为0.01 mg·kg~(-1)。以空白样品为基体进行加标回收试验,所得回收率为80.5%~98.7%,测定值的相对标准偏差(n=6)为5.0%~13%。     

固相萃取-高效液相色谱同时测定大米中的4种烟碱农药残留量

建立了高效液相色谱法同时测定大米样品中呋虫胺、噻虫胺、吡虫啉、吡虫清4种烟碱农药残留量的检测方法,对4种烟碱农药在ENVI-Florisil和Carb复合固相萃取柱上的保留行为进行了研究。样品用乙腈提取,固相萃取净化,HPLC-DAD分离检测,外标法定量。峰面积与标准溶液浓度在0.1～1.0 mg/L范围内呈良好的线性关系,相关系数大于0.9996。样品加标回收率为75.5%～96.0%,相对标准偏差为0.49%～4.36%(n=6),检出限达到0.004 mg/kg。     

羧甲基壳聚糖在果蔬保鲜中的应用研究进展

综述了羧甲基壳聚糖的特性及其在果蔬的涂膜保鲜中的应用研究进展,讨论了羧甲基壳聚糖的浓度、分子量、pH值、取代度对其特性的影响,介绍了羧甲基壳聚糖对果蔬的涂膜保鲜效果。本文对开发羧甲基壳聚糖在果蔬防腐保鲜方面的应用具有理论指导意义。     

基于稳定同位素的5种蔬菜产地真实性判别

为保护蔬菜产地真实性,以上海市场5种常见蔬菜(生菜、茼蒿、辣椒、番茄和黄瓜)为研究对象,应用单因素方差分析上海和其他产地蔬菜的 δ13 C、δ15 N、δ2 H和 δ18 O值差异,并通过主成分分析(PCA)和偏最小二乘判别分析(PLS-DA)建立上海地产蔬菜真实性判别模型.结果表明,上海地产5种蔬菜总的δ15 N、δ...     

Disappearance of dislodgable residues of methomyl from leaves and vegetables in Tamilnadu (India)

The dislodgable residues of methomyl from leaves and vegetables were determined by a single-step methanol extraction followed by reversed-phase HPLC. The residues on the bhendi vegetables and leaves were several times higher than on the brinjal vegetables and leaves. The pesticide, however, dissipates rapidly under the South Indian climatic conditions resulting in undetectable residues within three days of spraying.     

Determination of multiple antibiotics in leafy vegetables using QuEChERS–UHPLC–MS/MS

A modified quick, easy, cheap, effective, rugged, and safe method was established for simultaneous extraction and cleanup of multiple antibiotics in leafy vegetables, and ultra‐high performance liquid chromatography with tandem mass spectrometry was used for analysis. Antibiotics in leafy vegetables were extracted with citric acid/sodium citrate in mixed solvents consisting of acetonitrile/methanol (85:15, v/v) from 10 g of vegetables. Octadecylsilyl and graphitized carbon black were used as dispersant adsorbents. This method was able to effectively extract all of the target antibiotics from leafy vegetables. The average recoveries of 20 antibiotics ranged from 57 to 91%. The limits of detection were 0.33–2.92 μg/kg. The developed method subsequently demonstrated its selectivity, sensitivity, and reliability for detecting multiple antibiotics in 15 samples. Antibiotic residues in vegetables have attracted great concern with respect to human health. It is recommended that standards should be established for antibiotic residues in vegetables to ensure food safety.     

我国66种蔬菜矿质营养成分的综合评价

通过对我国66种常用新鲜蔬菜的K、Na、Ca、Mg、Fe、Mn、Zn、Cu、P、Se等10种矿质营养元素含量数据的深度挖掘,用聚类分析法建立了蔬菜的矿质营养成分谱。结果表明,66种蔬菜按其所含矿质元素含量的高低及其组合状况可有序地划分为6个组：即富K、P、Zn型蔬菜,富Ca蔬菜,富Mn、Fe、Se型蔬菜,富zn、Fe、P型蔬菜、各种营养成分的配合较为均衡的蔬菜和低K、P型蔬菜。按照蔬菜的w（Zn）／w（Cu）、w（Ca）／w（Mg）、w（Na）／w（K）比值序列,为人们尤其是高血压和冠心病患者科学合理地选择和搭配蔬菜提供了参考。     

Representative commodity for five brassica vegetables based on the determination and dissipation of six pesticide residues

A Quick, Easy, Cheap, Effective, Rugged and Safe method for determination of thiophanate-methyl, carbendazim, metalaxyl, fluazifop-P-butyl, chlorpyrifos and lambda-cyhalothrin in five brassica vegetables by high performance liquid chromatography-mass spectrometry/mass spectrometry and gas chromatography-electron capture detector has been developed. The average recoveries of six pesticides in five brassica vegetables were in the range of 77.4%–117.4% with relative standard deviation of 3.7–10.8%. Residues of thiophanate-methyl, carbendazim, metalaxyl, fluazifop-P-butyl, chlorpyrifos and lambda-cyhalothrin in five brassica vegetables were studied with the developed method for the classification of crop group and selection of representative commodity of five brassica vegetables. Totally 48 open field trials on five brassica vegetables were conducted at two locations in two different seasons. The residue dynamics and final residues of the six pesticides at three preharvest intervals in different vegetables were compared. All six pesticides had the longest half-lives in cabbage (2.1–3.5 days). Residues of carbendazim (sum of thiophanate-methyl and carbendazim), metalaxyl, chlorpyrifos and lambda-cyhalothrin had similar trend in different brassica vegetables. The maximal concentrations of these pesticide residues were found in kale (0.28–10.9 mg kg^?1). Fluazifop-P-butyl residues were at low levels in all five brassica vegetables (<0.01–0.03 mg kg^?1). Cabbage, red cabbage, Brussels sprouts and kohlrabi had no significant difference in all six pesticide residues and could be classified in a subgroup of Head Brassicas. Cabbage should be selected as the representative commodity. Considering the highest residues in kale and its different morphology, kale should not be classified into the subgroup of Head Brassicas.     

基质固相分散-液相色谱-质谱法测定蔬菜中的邻苯二甲酸酯

采用基质固相分散-液相色谱-质谱法测定保护地蔬菜中邻苯二甲酸酯(PAEs)含量,并分析了蔬菜中PAEs污染状况,研究了水和洗涤液浸泡对蔬菜中PAEs的消除效果。蔬菜样品经弗罗里硅土和石墨化碳黑研磨均匀后,用乙酸乙酯淋洗净化,再用液相色谱/电喷雾质谱法测定。PAEs的添加回收率为82.7%~105.7%;RSD为1.7%~6.1%;检出限为邻苯二甲酸二甲酯(DMP):0.99ng;邻苯二甲酸二乙酯(DEP):0.75ng;邻苯二甲酸二丁酯(DBP):0.70ng;邻苯二甲酸二异辛酯(DEHP):1.9ng。本方法前处理简单,具有较高的准确度和灵敏度。黄瓜、番茄、西葫芦中4种PAEs总量分别为2.02、1.26、0.91mg/kg;洗涤实验结果表明,水和洗涤液浸泡可显著降低蔬菜中的PAEs含量。     

Elemental composition of vegetables cultivated in illegal mining towns in Ghana using neutron activation analysis

The elemental concentrations of 12 elements from five species of the most consumed vegetables in Ghana cultivated in five mining and three non-mining towns have been analyzed using neutron activation analysis. About 50% of the total concentrations recorded for cadmium and arsenic for the various towns and vegetables were found to be above the World Health Organization (WHO) permissible levels. The statistical methods employed in this work also provided more understanding on the geographical distribution of the elements, vegetables and sampling towns. The principal component analysis of our data showed two major clusters consisting of gold mining towns and non-gold mining towns in relation to the elemental concentrations of vegetables cultivated in these towns.     

基于QuEChERS提取方法优化的液相色谱-串联质谱法测定蔬菜中51种氨基甲酸酯类农药残留

采用气相色谱-质谱（GC-MS）全扫描结合NIST谱库检索方法分析6种蔬菜（番茄、青刀豆、大葱、青花菜、姜、胡萝卜）提取液中的基质干扰物,以蒸发残渣重量法探讨乙二胺N-丙基硅烷（PSA）、十八烷基硅烷（C18）及两者组合对6种蔬菜提取液基质干扰物的净化效果及吸附机理,考察了原创QuEChERS方法及AOAC 2007.01方法对蔬菜中51种氨基甲酸酯类农药提取的适用性,并建立了液相色谱-串联质谱法测定蔬菜中51种氨基甲酸酯类农药残留的方法。结果表明,C18与PSA组合进行分散固相萃取的净化效果最好;AOAC 2007.01方法适用于二氧威以外的50种农药残留的提取,而原创QuEChERS方法对二氧威残留的提取可获得满意结果。经电喷雾正离子电离及多反应监测模式来测定目标化合物,采用基质匹配标准溶液曲线法进行定量。结果表明：51种农药在6种基质中3个添加水平（10、20、100 μg/kg）的回收率为58.4%~126%,相对标准偏差为3.3%~26%;以信噪比（S/N）≥10计,久效威及杀螟丹的定量限（LOQ）为50 μg/kg,其他49种农药的LOQ为0.2~10 μg/kg。本文方法有效、灵敏,适用于不同蔬菜基质中51种氨基甲酸酯类农药残留的测定。     

Pesticide residue determination in vegetables from western China applying gas chromatography with mass spectrometry

In this study,an effort has been made to evaluate the pesticide residues in vegetables from western China. Fifty‐one pesticides, including organophosphorus, organochlorine, carbamate and pyrethroid, were detected in 369 commonly used vegetables by GC‐MS. Concentrations of organophosphorus pesticides were detected ranging from 0.0008 to 18.8200 mg/kg, among which organophosphorus pesticide concentrations exceeded their maximum residue levels (MRLs) in five samples. Carbamate and organochlorine pesticides were determined to have concentrations in the range of 0.0012–0.7928 mg/kg. The residual concentrations of carbamate pesticides in six samples and organochlorine pesticides in four samples exceeded their MRLs. The residual concentrations of five pyrethroid pesticides were within the range of 0.0016–6.0827 mg/kg and the pyrethroid residues in two samples exceeded their MRLs. The results revealed that pesticide residues in 70.73% of the vegetables samples were not detected, while in the rest of vegetables there were one or more pesticide residues and some even exceeded their MRLs, which would threaten the health of consumers. Our work provides significant information for the food safety regulations to control the excessive use of some pesticides on those kinds of vegetables from western China. Copyright © 2016 John Wiley & Sons, Ltd.