固相萃取/高效液相色谱法测定地表水中磺酰脲类农药的研究

建立了固相萃取/高效液相色谱法(SPE/HPLC)同时测定地表水中五种磺酰脲类农药的方法。研究了固相萃取提取、净化方法,优化了高效液相色谱条件并用二极管阵列检测器进行定量分析。五种磺酰脲类农药在0.1~10.0μg/mL范围内线性良好,相关系数在0.9992~0.9998之间,相对标准偏差在1.8%~4.1%之间,平均回收率为72.8%~103%。本方法中五种磺酰脲类农药的检出限在0.02~0.22 ng/mL范围。用该法分析了某水域地表水,取得满意结果,表明本方法具有一定的实用性。     

蔬菜中苯甲酰脲类药物残留的测定方法研究

建立了一步有机溶剂提取、HPLC分离、紫外检测器检测7种苯甲酰脲类药物(除虫脲、灭幼脲、杀铃脲、氟铃脲、氟苯脲、氟虫脲和氟啶脲)在蔬菜中残留量的方法。考察了不同提取溶剂(乙酸乙酯和乙腈)的提取效率;研究了不同C18固相萃取小柱、活性碳、自制弗罗里硅土柱和GPC对蔬菜样品的净化效果;实验了不同的梯度淋洗程序分离7种药物。通过对黄瓜、大白菜、西红柿和包心菜4种蔬菜的4种添加水平和4次重复性实验,建立了一种以乙腈为提取溶剂和以弗罗里硅土柱为净化柱的高效液相色谱法测定7种苯甲酰脲类药物。该方法线性范围为:0.02~1.5mg/L,7种苯甲酰脲类药物的相关系数均大于0.999,其检出限为0.02~0.05mg/kg(S/N=10);在0.05~1.0mg/kg之间的添加回收率为80%~120%;相对标准偏差小于15%。方法完全符合残留分析的要求。     

基于十八烷基三甲基溴化铵修饰的磁性粒子在线磁性固相萃取-高效液相色谱法测定水样中磺酰脲类农药

采用溶胶-凝胶法制备表面修饰了十八烷基三甲基溴化铵的磁性粒子作为萃取剂，研制了一种在线磁性固相萃取（on-line MSPE）装置，建立了on-line MSPE与高效液相色谱联用测定水样中两种磺酰脲类农药（氯磺隆、苄嘧磺隆）的方法。实验优化了在线磁性固相萃取条件并进行方法学考察，证明该方法具有良好的线性关系（两种目标物的线性相关系数均≥ 0.9997）和较低的检出限（两种目标物的检出限分别为0.32和1.12 μg/L）。将此法用于3种环境水样中两种磺酰脲类农药的检测，水样中均检出氯磺隆，均未检出苄嘧磺隆。两种目标物加标回收率为70.0%~113.4%。该方法高效、简便，在分离富集环境水样中磺酰脲类农药方面有一定的应用前景。     

高效液相色谱-串联质谱法测定大豆与玉米中的苯甲酰脲类农药残留

建立了大豆和玉米中苯甲酰脲类农药的反相高效液相色谱-电喷雾串联质谱(LC-ESIMS/MS)检测方法。样品经含0.1%乙酸的乙腈提取、浓缩,阳离子固相萃取柱净化,液相色谱串联质谱测定。9种苯甲酰脲类农药在5.0～200μg/L范围内线性关系良好(r20.995)。在大豆和玉米基质中的检出限均为3.0μg/kg,定量下限均为10.0μg/kg。在10.0、20.0、50.0μg/kg 3个加标水平下,9种苯甲酰脲类农药的回收率为46%～92%,精密度(RSD)小于14%。方法准确、灵敏、简单,适用于大豆和玉米中9种苯甲酰脲类农药残留的同时测定。     

果蔬中8种苯甲酰脲类农药残留量的液相色谱-串联质谱法测定

建立了果汁蔬菜中8种苯甲酰脲类(杀虫脲、氟苯脲、氟虫脲、氟啶脲、除虫脲、氟铃脲、灭幼脲、氟丙氧脲)农药残留量的液相色谱-电喷雾串联质谱(LC-ESI MS/MS)测定方法。样品用乙腈提取后无需净化,经盐析过滤并以水稀释(1∶1)后,经Waters Atlantis(d C18色谱柱分离,5 mmol/L乙酸铵水溶液和乙腈梯度洗脱,以电喷雾电离串联质谱在负离子多反应监测(MRM)模式下进行测定并确证,外标法定量。8种苯甲酰脲类农药在1.0~100μg/L范围内线性良好,相关系数为0.990 0~0.999 9。对8种农药在毛豆基质中3个添加水平下的回收率进行测定,平均回收率为92%~110%,相对标准偏差为5.5%~12%。方法的检出限(S/N=3)为0.04~0.42μg/kg,定量下限(S/N=10)为0.2~1.5μg/kg。     

ZIF-8@Fe_3O_4磁性固相萃取结合高效液相色谱法测定果汁中3种苯甲酰脲杀虫剂

发展了磁性沸石咪唑酯骨架材料(ZIF-8@Fe_3O_4)磁性固相萃取结合高效液相色谱-二极管阵列检测器,测定果汁中氟幼脲、四螨嗪和氟啶脲3种苯甲酰脲杀虫剂(BUs)的新方法。利用X射线衍射仪、傅立叶变换红外光谱仪、扫描电子显微镜和振动样品磁强计对合成的ZIF-8@Fe_3O_4吸附剂进行表征,考察了溶液pH值、吸附剂用量、吸附时间、洗脱溶剂种类和体积(单次洗脱体积×洗脱次数)对BUs萃取效率的影响。在最优实验条件下,氟幼脲和四螨嗪在2.0～200 ng/mL、氟啶脲在3.5～350 ng/mL范围内线性关系良好(相关系数r=0.999),检出限(S/N=3)和定量下限(S/N=10)分别为0.6～1.0 ng/mL和2.0～3.5 ng/mL。3个加标水平下的回收率为82.7%～98.6%,日内和日间(n=3)相对标准偏差(RSD)分别为1.2%～6.1%和1.3%～9.0%。当上样体积为10 mL时,ZIF-8@Fe_3O_4对果汁中3种BUs的富集倍数为43.4～48.1倍,吸附剂重复使用10次后,3种BUs回收率的RSD不大于8.8%。该方法灵敏、高效,可用于果汁样品中BUs的分析。     

双酚A分子印迹聚合物为萃取介质搅拌饼固相萃取的制备及其萃取性能研究

以双酚A为模板,4-乙烯基吡啶为单体,利用整体材料"原位"聚合技术制备分子印迹聚合物为基质的萃取饼,并与利用一次性注射器空管加工而成的萃取器相结合,建立了分子印迹搅拌饼固相萃取(MIP-SCSE)技术。考察了制备条件对MIP-SCSE选择吸附性能的影响。在此基础上,与高效液相色谱-二极管阵列检测器联用,探讨MIP-SCSE对环境水样中双酚A及其它酚类物质的选择萃取性能,考察萃取过程中基底离子强度、pH值以及吸附与解吸时间等萃取条件对萃取性能的影响。结果表明;在最佳萃取条件下,MIP-SCSE对模板分子及其它酚类物质具有一定选择性能和较高的富集能力,对双酚A的线性范围为1.0～200μg/L;检出限LOD(S/N=3)为0.67μg/L;定量限LOQ(S/N=10)为2.24μg/L。在实际水样分析中,模板分子加标回收率为86.2%～112.2%。在MIP-SCSE使用过程中,萃取饼不与容器壁接触,因此具有优良的使用寿命,至少可连续使用600 h。     

分子印迹固相萃取-高效液相色谱法同时检测烟叶中磺酰脲类农药残留

以氯磺隆（CS）为模板分子,甲基丙烯酸为功能单体,三羟甲基丙烷三甲基丙烯酸酯为交联剂,在二氯甲烷氛围中,经沉淀聚合制备氯磺隆分子印迹聚合物（CS-MIP）微球。将该聚合物微球作为填料制得分子印迹固相萃取柱用于样品前处理,建立了分子印迹固相萃取-高效液相色谱（MIP-SPE-HPLC）同时检测烟叶中6种磺酰脲类除草剂残留的分析方法。针对氯磺隆、甲磺隆、苄嘧磺隆、苯磺隆、胺苯磺隆和烟嘧磺隆6种磺酰脲类除草剂,在烟叶中加标0.50~50 μg/g,经氯磺隆分子印迹固相萃取柱（CS-MIP-SPE）净化和富集,高效液相色谱（HPLC）检测,其平均回收率为77.60%~102.05%,相对标准偏差为0.16%~7.07%,检出限为0.08~0.46 μg/g。将MIP-SPE-HPLC方法用于实际农药残留检测,结果表明可同时满足烟叶中多种磺酰脲类除草剂残留量的检测要求。     

Fe3O4/g-C3N4磁性固相萃取湖水中的3种苯甲酰脲杀虫剂

建立了Fe3O4/g-C3N4磁性固相萃取,结合高效液相色谱-可变波长紫外检测,用于测定湖水中3种苯甲酰脲杀虫剂的新方法.实验考察了溶液pH、离子强度、吸附剂用量、吸附时间、洗脱溶剂种类和体积对3种目标物回收率的影响.在最优实验条件下,氟铃脲和虱螨脲在0.50～500 ng/mL(r≥0.9997)、氟啶脲在0.20～...     

固相膜萃取/高效液相色谱法测定环境水体中的磺酰脲类除草剂

建立了一种基于C₁₈固相萃取膜预富集、高效液相色谱法定量分析环境水体中6种痕量磺酰脲类除草剂的快速分析方法。优化了色谱分离条件,考察了洗脱剂种类与体积、水样pH值和盐效应等条件对萃取效率的影响。在优化条件下,6种磺酰脲类除草剂的峰面积与其质量浓度呈良好的线性关系,苯磺隆的线性范围为0.10²0.0μg/L,其余均为0.05²0μg/L,相关系数为0.999 0⁰.999 5,方法检出限为0.019⁰.037μg/L。对地表水和海水的加标回收率分别为92.6%¹05.7%和89.8%¹08.7%,相对标准偏差分别为0.7%⁷.1%和0.5%⁴.0%。该方法操作简单、快速、准确、灵敏度高。     

Extraction of trace nitrophenols in environmental water samples using boronate affinity sorbent

In this research, the applicability of a new sorbent based on boronate affinity material is demonstrated. For this purpose, six strong polar nitrophenols were selected as models which are difficult to be extracted in neutral form (only based on hydrophobic interactions). The extracted nitrophenols were separated and determined by high-performance liquid chromatography with diode array detection. The sorbent was synthesized by in situ copolymerization of 3-acrylamidophenylboronic acid and divinylbenzene using dimethyl sulfoxide and azobisisobutyronitrile as porogen solvent and initiator, respectively. The effect of the preparation parameters in the polymerization mixture on extraction performance was investigated in detail. The size and morphology of the sorbent have been characterized via different techniques such as infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. The important parameters influencing the extraction efficiency were studied and optimized thoroughly. Under the optimum extraction conditions, the limits of detection (S/N = 3) and limits of quantification (S/N = 10) for the target nitrophenols were 0.097–0.28 and 0.32–0.92 μg/L, respectively. The precision of the proposed method was evaluated in terms of intra- and inter-assay variability calculated as RSD, and it was found that the RSDs were all below 9%. Finally, the developed method was successfully applied for environmental water samples such as wastewater, tap, lake and river water. The recoveries varied within the range of 71.2–115% with RSD below 11% in all cases. The results well demonstrate that the new boronate affinity sorbent can extract nitrophenols effectively through multi-interactions including boron–nitrogen coordination, hydrogen-bond and hydrophobic interactions between sorbent and analytes.     

基于整体材料搅拌棒固相萃取高效液相色谱联用测定饲料和水样中硝基呋喃类药物残留

利用自制的以聚(乙烯基咪唑-二乙烯基苯)(VIDB)整体材料为涂层的固相萃取搅拌棒(VIDB-SBSE)萃取3种硝基呋喃类药物,然后与高效液相色谱-二极管阵列检测器联用建立了测定饲料和水样品中硝基呋喃类药物残留的方法。详细考察了萃取过程中萃取和解吸时间、样品基质的pH值以及离子强度等实验条件对萃取效率的影响。在最佳条件下,呋喃唑酮的线性范围为0.5~200μg/L,呋喃妥因和呋喃西林的线性范围为0.25~200μg/L,3种目标物的检出限(LO D)(S/N=3)在0.068~0.11μg/L之间,所建方法具有理想的日内和日间重现性(R SD值均小于6%)。在对饲料和实际水样的测定中,不同加标浓度呋喃唑酮、呋喃妥因和呋喃西林的回收率在80.6%~108%之间。研究表明,所建立的方法具有简便、灵敏、环境友好等特点。     

支链聚乙烯亚胺辅助硼酸功能化磁性纳米粒子的制备及其用于人参皂苷的特异性富集

为了实现更高效的人参皂苷富集,以硼亲和色谱为核心,结合支链聚乙烯亚胺放大硼酸配基数量,合成了支链聚乙烯亚胺辅助硼酸功能化磁性纳米粒(PEI-BA-MNPs),用于实际样品中人参皂苷的选择性富集,结合高效液相色谱,建立了一种分析实际样品中的人参皂苷的方法.以人参皂苷Re为代表,在优化的磁性固相萃取的条件下,该方法在50～...     

Magnetic solid‐phase extraction of benzoylurea insecticides in tea samples with Fe3O4‐hyperbranched polyester magnetic composite as sorbent

In this work, a method for the analysis of benzoylurea insecticides, including hexaflumuron, flufenoxuron, lufenuron and chlorfluazuron, in tea samples by high‐performance liquid chromatography with Fe₃O₄‐hyperbranched polyester nanocomposite as the adsorbent for magnetic solid‐phase extraction was developed. The magnetic nanocomposite was prepared and characterized by infrared spectroscopy, vibrating sample magnetometry, and scanning electron microscopy. The as‐prepared nanocomposite was used as a sorbent for the extraction and preconcentration of pesticide residues in tea samples. The extraction and desorption conditions, including mass ratios of raw materials, amount of sorbent, pH value, extraction time, and desorption time, were investigated. Under the final conditions chosen for the analysis, good linearity was obtained for all the tested compounds, with R² values of at least 0.9979. The limits of detection were determined in the range of 0.15–0.3 μg/L. The recovery obtained from the analysis of tea samples with various spiked concentrations was between 90.7 and 98.4%, with relative standard deviations (n = 4) lower than 4.1%. Furthermore, the present approach was successfully applied to the quantitative determination of residues of benzoylurea insecticides in real samples.     

基于氧化石墨烯气凝胶固相萃取柱检测有机磷农药北大核心CSCD

以氧化石墨烯气凝胶三维纳米材料作为固相萃取的吸附剂,结合高效液相色谱,对食品中的有机磷农药(辛硫磷、双硫磷、倍硫磷、杀螟硫磷)进行检测分析。首先,利用冷冻干燥的方式制备得到氧化石墨烯气凝胶,通过扫描电镜、红外光谱、比表面积吸附等一系列的实验手段对其形貌及物理特性进行了表征,证明其成功合成。从扫描电镜中可见石墨烯的层状褶皱结构,其表面积为740.51 m^(2)/g。然后,将氧化石墨烯气凝胶直接填充于固相萃取柱中,在未借助任何硅胶等基体的条件下进行萃取研究;通过单因素实验,系统研究了萃取和洗脱条件对有机磷农药萃取回收率的影响。结果显示,在上样体积15 mL、样品溶液pH值4、上样速率1.0 mL/min、洗脱剂1.0 mL乙腈的条件下萃取回收率最高。与商用的萃取材料进行比较,包括碳十八硅胶柱(C18)、阴离子交换柱(SAX)、氨基柱(-NH_(2))和硅酸镁柱(Florisil),氧化石墨烯气凝胶填充的固相萃取柱的萃取回收率有明显提高。实验考察了氧化石墨烯气凝胶直接填充的萃取柱的寿命,结果显示该萃取柱可以重复使用15次,可见解决了分散无基体支撑的石墨烯纳米片容易破碎、堵塞筛板的问题。与液相色谱联用建立分析方法,4种有机磷农药的线性范围较宽,辛硫磷、双硫磷和倍硫磷的线性范围为1~200μg/L,杀螟硫磷的线性范围为2~200μg/L,线性拟合良好(线性相关系数r^(2)≥0.9949),检出限为0.2~0.5μg/L,满足于我国和其他国家限定标准的检测。将该方法应用于实际样品,在苹果皮中未检测到有机磷农药,对其进行加标,回收率为70.5%~93.6%,相对标准偏差≤10.4%。     

分子印迹聚合物为涂层的吸附萃取搅拌棒在环境水样双酚A含量测定中的应用

以双酚A(BPA)为单体,利用整体材料“原位”聚合技术制备以分子印迹聚合物为涂层的吸附萃取搅拌棒(MIP-SBSE),然后与高效液相色谱(HPLC)-二极管阵列检测器联用,探讨其对环境水样BPA的选择萃取性能。优化萃取过程中吸附和解吸时间、解吸液种类以及基底pH值和离子强度对目标化合物的选择吸附性能。在最佳条件下,MIP-SBSE可对模板分子进行有效的选择吸附,线性范围为1.0～200 μg/L,检出限(S/N=3)和定量限(S/N=10)分别为0.28μg/L和0.94 μg/L。在实际水样分析中,具有良好的加标回收率,其值为96.0%～108.7%。研究结果表明,所建立的方法具有简便、灵敏和环境友好等特点。     

管内硼亲和固相微萃取-高效液相色谱全自动在线联用检测茶饮料中的顺式二羟基化合物

自动化联用分析技术对于降低人力强度、提高效率和保证数据重现性等具有重要意义。硼亲和固相微萃取(BA-SPME)是近十年出现的用于富集顺式二羟基化合物的独特工具,但BA-SPME与高效液相色谱(HPLC)的自动化在线联用还未见报道。该文报道了一种新颖的管内BA-SPME-HPLC全自动在线联用方法,用于分析茶饮料中的顺式二羟基化合物。该自动化在线联用方法利用自动进样器通过六通阀的切换实现流路连接。制备了管内BA-SPME毛细管,考察了涂层柱的柱容量,并对其形貌进行了表征,考察并优化了影响实际样品分离效果的因素。最后,利用该联用方法对3种不同品牌的茶饮料进行了分析,并对沏茶温度对茶水中顺式二羟基化合物含量的影响进行了评价。     

改性多壁碳纳米管固相萃取-高效液相色谱法测定农产品中痕量残留的4种有机氯农药

对多壁碳纳米管(MWNTs)的表面进行酸氧化处理制备了改性的MWNTs,并建立了以改性MWNTs作为固相萃取(SPE)吸附剂测定农产品中痕量残留的4种有机氯农药(p,p′-DDD、p,p′-DDT、o,p′-DDT、p,p′-DDE)的SPE-高效液相色谱(HPLC)分析方法。考察了氧化处理条件、SPE操作条件和色谱条件等对有机氯农药残留测定的影响,优化了实验条件。在优化实验条件下,4种农药在较宽线性范围内线性良好,相关系数为0.9978～0.9995,检出限为0.050 mg/L;在样品中分别添加0.10、2.0、50 mg/L的4种农药,其加标回收率为78%～104%,相对标准偏差(RSD)为2.7%～7.6%。MWNTs作为SPE填料用于陈皮、西洋参、卷心菜和茶叶等样品的净化效果良好,测定结果准确,灵敏度高,符合农产品中痕量农药残留的分析方法要求,为农产品中此类农药的痕量残留分析提供了有益的参考。     

硼酸亲和整体柱在富集中药活性物质中的应用

以4-乙烯基苯硼酸(VPBA)为功能单体,季戊四醇三丙烯酸酯(PETA)为交联剂,乙二醇和二甘醇为二元致孔剂,通过热引发自由基聚合反应,在毛细管内原位聚合制备得到一种poly(VPBA-co-PETA)毛细管整体柱。所制备的整体柱具有典型的硼酸亲和特性,可以特异性地捕获含有顺二羟基的化合物。在前期实验的基础上,将其用于两种中草药 蒲公英和刺果卫矛中含顺二羟基的小分子活性物质的富集。这两种中药提取物直接用高效液相色谱进行检测时,其活性成分绿原酸等因含量太低而使检测困难或无法检测;经过硼酸亲和整体柱富集后收集洗脱液进行检测,色谱峰响应则显著提高。该结果表明所制备的poly(VPBA-co-PETA)整体柱可以作为富集中药提取物中含顺二羟基活性物质的有效手段。     

Preparation of a polymeric ionic liquid-based adsorbent for stir cake sorptive extraction of preservatives in orange juices and tea drinks

In this study, a new polymeric ionic liquid-based adsorbent was prepared and used as the extraction medium of stir cake sorptive extraction (SCSE) of three organic acid preservatives, namely, p-hydroxybenzoic acid, sorbic acid and cinnamic acid. The adsorbent was synthesized by the copolymerization of 1-ally-3-vinylimidazolium chloride (AV) and divinylbenzene (DVB) in the presence of a porogen solvent containing 1-propanol and 1,4-butanediol. The effect of the content of monomer and the porogen solvent in the polymerization mixture on the extraction performance was investigated thoroughly. The adsorbent was characterized by infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. To obtain the optimal extraction conditions of SCSE/AVDVB for target analytes, key parameters including desorption solvent, adsorption and desorption time, ionic strength and pH value in sample matrix were studied in detail. The results showed that under the optimized conditions, the SCSE/AVDVB could extract the preservatives effectively through multiply interactions. At the same time, a simple and sensitive method by combining SCSE/AVDVB and high-performance liquid chromatography with diode array detection was developed for the simultaneous analysis of the target preservatives in orange juices and tea drinks. Low limits of detection (S/N = 3) and quantification limits (S/N = 10) of the proposed method for the target analytes were achieved within the range of 0.012–0.23 μg/L and 0.039–0.42 μg/L, respectively. The precision of the proposed method was evaluated in terms of intra- and inter-assay variability calculated as relative standard deviation (RSD), and it was found that the values were all below 10%. Finally, the proposed method was used to detect preservatives in different orange juice and tea drink samples successfully. The recoveries were in the range of 71.9–116%, and the RSDs were below 10% in the all cases.