Determination of Chlorogenic Acid and Rutinum in Herba Artemisiae Scopariae with Multitemplate Molecularly Imprinted Polymers for Solid-phase Extraction with High-performance Liquid Chromatography

Novel multitemplate molecularly imprinted polymers were prepared using mixtures of chlorogenic acid and rutinum as molecular templates, acrylamide as a functional monomer, divinylbenzene as the cross-linker, and 20:80 methanol:acetone as the porogen. The polymers were assessed for solid-phase extraction (SPE) for the purification of two compounds from Herba Artemisiae Scopariae. The synthesized molecularly imprinted polymers were identified by infrared spectroscopy and scanning electron microscopy. Systematic characterization of the functional monomer and porogens on the recognition properties of the molecularly imprinted polymers were carried out. Comparison with single-template molecularly imprinted polymers showed that the multitemplate molecular polymers exhibited higher selectivity and adsorption capacity for multiple analytes. The optimization of washing solvent as 1:9 acetone:water and the elution solvent as 9:1 acetonitrile:acetic acid provided a reliable analytical method with strong recognition toward multiple analytes in Herba Artemisiae Scopariae extracts with satisfactory recoveries of 89.6% for chlorogenic acid and 93.8% for rutinum. These results demonstrate that the multitemplate molecularly imprinted polymers coupled with SPE are effective for the selective purification of bioactive compounds in complex samples.     

Magnetic Molecularly Imprinted Polymer Preconcentration of 4-Chlorophenol with Determination by High-Performance Liquid Chromatography

A novel magnetic dummy molecularly imprinted polymer based on multiwalled carbon nanotubes was prepared with 2-amino-4-chlorophenol as the dummy template for rapid separation and enrichment of 4-chlorophenol in aqueous samples. The magnetic dummy molecularly imprinted polymer was characterized by infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, and vibrating sample magnetometry. The saturation adsorption capacity of the magnetic dummy molecularly imprinted polymer toward 4-chlorophenol was up to 54.3?mg?g^?1 at 298?K, which is higher than for previously reported imprinted polymers. The magnetic dummy molecularly imprinted polymers were coupled with high-performance liquid chromatography to isolate and determine 4-chlorophenol in fish bile and river water with the recoveries from 95.8 to 98.9% and 96.6 to 99.1%, respectively.     

分子印迹磁性固相萃取/液相色谱法检测奶制品中的双酚A

以双酚A(BPA)为模板分子,磁性二氧化硅(Fe_3O_4@SiO_2)为载体,4-乙烯基吡啶(4-VP)为功能单体,采用表面分子印迹技术制备了双酚A磁性分子印迹聚合物微球(Fe_3O_4@SiO_2-MIPs)。通过红外光谱、透射电镜等对Fe_3O_4@SiO_2-MIPs进行了结构和形貌的表征。将制得的Fe_3O_4@SiO_2-MIPs作为磁性吸附剂,分离富集奶制品中的BPA,建立了分子印迹磁性固相萃取/液相色谱法测定奶制品中BPA的新方法。结果表明,在优化条件下,Fe_3O_4@SiO_2-MIPs对BPA具有良好的选择性,最大吸附容量达13.50 mg/g,在0.05~5.0 mmol/L浓度范围内有良好的线性关系(r2=0.993 4),方法检出限为0.037μg/L,样品加标回收率为86.2%~93.1%,相对标准偏差为2.9%~3.8%。该方法高效快速,选择性好,可用于牛奶样品中痕量BPA的检测。     

固相萃取/高效液相色谱法测定茶油中的多种天然酚类物质

建立了同时分离、检测茶油中23种酚类物质的高效液相色谱方法.比较了液液萃取、固相萃取两种方法的提取效果,并优化了流动相、检测波长、进样量等参数.23种酚类物质在优化条件下均可有效分离,并在0.059～9.115μg/g范围内具有良好的线性关系,相关系数为0.9776～1.0000,检出限为0.041～0.379μg/g...     

分子印迹固相萃取-高效液相色谱法测定蜂蜜中三种氟喹诺酮类抗生素残留

采用沉淀聚合法,以诺氟沙星为模板分子,合成了对氟喹诺酮类(FQs)抗生素特异性识别的分子印迹聚合物(MIPs),其印迹因子为3.17,亲和位点总数为3.27μmol/g。以该MIPs做为固相萃取柱填料,建立了分子印迹固相萃取-高效液相色谱检测蜂蜜中三种FQs抗生素残留的方法。与Oasis HLB固相萃取柱相比,该分子印迹固相萃取柱(MISPE)具有更好的净化能力和更高的富集效率。最佳条件下,三种FQs抗生素的线性范围为0.125～12.5mg/kg,相关系数均大于0.999。方法的检出限(S/N=3)为9～12μg/kg,三种FQs抗生素的加标回收率为96.5%～104.1%,相对标准偏差不高于6.2%(n=5)。该方法有望用于蜂蜜中FQs抗生素残留的常规检测。     

Determination of Tetracyclines by Solid-Phase Extraction with a Molecularly Imprinted Polymer and High-Performance Liquid Chromatography

Tetracyclines are widely used antibiotics classified as emerging pollutants and may lead to an increase in bacterial resistance in the environment. In order to determine these compounds at low concentrations, a water-compatible molecularly imprinted polymer was developed for solid-phase extraction followed by high-performance liquid chromatography analysis. The monomers 2-hydroxyethyl methacrylate and glycerol dimethacrylate were added 1 h after the start of the synthesis to provide hydroxyl groups on the polymer surface. This hydrophilic layer established hydrogen bonds with water, minimizing interferences of this solvent in the analyte-polymer complex, increasing analyte adsorption. The polymer was then used for solid-phase extraction to preconcentrate the tetracyclines. The method provided low limits of quantification (5 µg L^?1), good linearity, precision, and accuracy for tetracyclines, with preconcentration factors of 14, 19, 29, and 41 for oxytetracycline, tetracycline, chlortetracycline, and doxycycline, respectively.     

磁性分子印迹聚合物萃取/高效液相色谱检测蔬菜中的灭多威

以磁性分子印迹聚合物为吸附剂,建立了蔬菜中灭多威的快速、选择性分析方法。以灭多威为模板分子,甲基丙烯酸为功能单体,二甲基丙烯酸乙二醇酯为交联剂,Fe3O4为磁性组分制备该聚合物。通过红外光谱、扫描电镜以及综合物性测量仪对合成的聚合物进行表征。Scatchard分析表明磁性分子印迹聚合物对灭多威有两种结合方式,最大表观吸附量(Qmax)和平衡离解常数(Kd)分别为Qmax1=0.053 04 mmol/g,Kd1=0.314 35 mmol/L;Qmax2=0.130 51 mmol/g,Kd2=1.921 22 mmol/L。动力学结果显示该聚合物对灭多威的吸附符合准二级动力学模型。与其它物质相比,制备的聚合物对灭多威具有高选择性识别性能。考察了萃取溶剂、聚合物用量、萃取时间、振荡速度、解析溶剂对灭多威回收率的影响。采用高效液相色谱对灭多威进行检测,检出限为0.012 mg/kg,RSD为2.2%～6.1%,加标回收率为86%～94%。该方法应用于检测甘蓝、小白菜、西红柿、黄瓜和辣椒中的灭多威。结果显示在西红柿样品中检出有灭多威,其含量为1.135 mg/kg。与传统的方法相比,该方法快速、有效,在食品农药残留的分析中具有很好的前景。     

克百威分子印迹固相萃取微球的制备及性能

以偶氮二异丁腈为引发剂,2~3μm的聚苯乙烯微球为种球,克百威为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,采用单步溶胀法制备粒径均一的克百威分子印迹聚合物微球(MIPMs)。通过扫描电镜(SEM)、吸附平衡实验和竞争吸附实验分析了克百威MIPMs的形貌及其对克百威的结合特性及吸附选择性,并比较了克百威分子印迹固相萃取柱(MISPE)与C18固相萃取柱(C18SPE)富集水中克百威的效果。结果表明:合成的MIPMs粒径约10μm,表面呈蜂窝状;在90min内可达到饱和吸附,最大吸附量为25.94mg/g;在克百威、灭多威和三羟基克百威共存的条件下,克百威MIPMs可实现对克百威的专一性吸附;与C18SPE相比,克百威MISPE重复使用6次后加标回收率仍在85%以上,可用于水体中痕量克百威的检测。     

反式白藜芦醇双功能单体印迹固相萃取柱的制备及应用

采用自组装技术,分别以β-环糊精和甲基丙烯酸为功能单体,反式白藜芦醇为模板分子,乙二醇二甲基丙烯酸酯为交联剂,制备了一种双功能单体印迹聚合物。 并将其作为固相萃取材料萃取红酒和白酒酒样中的反式白藜芦醇。 结果表明,与单功能印迹材料和非印迹材料相比,这种双功能单体印迹材料具有更高的吸附容量和选择性;结合高效液相色谱,建立了酒样中反式白藜芦醇浓度的检测方法。 该方法的线性范围在0.003~2 mg/L,红酒的回收率在87.9%~93.2%,白酒的回收率在89.3%~91.2%,检测限为0.001 mg/L。     

Magnetic Molecularly Imprinted Polymers for the Rapid and Selective Extraction and Detection of Methotrexatein Serum by HPLC-UV Analysis

In this work, novel selective recognition materials, namely magnetic molecularly imprinted polymers (MMIPs), were prepared. The recognition materials were used as pretreatment materials for magnetic molecularly imprinted solid-phase extraction (MSPE) to achieve the efficient adsorption, selective recognition, and rapid magnetic separation of methotrexate (MTX) in the patients’ plasma. This method was combined with high-performance liquid chromatography–ultraviolet detection (HPLC–UV) to achieve accurate and rapid detection of the plasma MTX concentration, providing a new method for the clinical detection and monitoring of the MTX concentration. The MMIPs for the selective adsorption of MTX were prepared by the sol–gel method. The materials were characterized by transmission electron microscopy, Fourier transform-infrared spectrometry, X-ray diffractometry, and X-ray photoelectron spectrometry. The MTX adsorption properties of the MMIPs were evaluated using static, dynamic, and selective adsorption experiments. On this basis, the extraction conditions were optimized systematically. The adsorption capacity of MMIPs for MTX was 39.56 mgg⁻¹, the imprinting factor was 9.40, and the adsorption equilibrium time was 60 min. The optimal extraction conditions were as follows: the amount of MMIP was 100 mg, the loading time was 120 min, the leachate was 8:2 (v/v) water–methanol, the eluent was 4:1 (v/v) methanol–acetic acid, and the elution time was 60 min. MTX was linear in the range of 0.00005–0.25 mg mL⁻¹, and the detection limit was 12.51 ng mL⁻¹. The accuracy of the MSPE–HPLC–UV method for MTX detection was excellent, and the result was consistent with that of a drug concentration analyzer.     

分子印迹固相萃取/高效液相色谱法分离和富集枳实中4种黄烷酮

采用沉淀聚合法以橙皮素为模板分子,2-乙烯基吡啶为功能单体,二甲基丙烯酸乙二醇酯为交联剂,合成了橙皮素分子印迹聚合物。利用紫外光谱法确定了最佳功能单体与配比,优化了合成条件。采用傅立叶变换红外光谱、扫描电子显微镜、静态吸附对聚合物进行表征。实验结果表明,分子印迹聚合物的吸附性能明显优于空白印迹聚合物,且此聚合物对柚皮苷、橙皮苷、柚皮素和橙皮素的相对选择系数分别为1.40,1.39,1.59和2.89,表明该分子印迹聚合物对4种黄烷酮有较好的选择性。将印迹聚合物作为固相萃取填料,对枳实提取液进行分离和富集,结果表明上述4种黄烷酮的提取率分别为72.6%,61.1%,95.4%和93.5%,分离富集效果良好,大大提高了枳实中4种黄烷酮的提取效率。     

类特异性分子印迹固相萃取/高效液相色谱法分析马尿泡果实中4种托烷类生物碱

以樟柳碱(ASD)为模板分子,甲基丙烯酸(MAA)为功能单体,三羟甲基丙烷三甲基丙烯酸酯(TRIM)为交联剂,乙腈为致孔剂,采用沉淀聚合法,合成了对4种托烷类生物碱(樟柳碱、东莨菪碱、山莨菪碱、阿托品)具有类特异性识别能力的聚合物。通过紫外光谱预测法筛选了最佳功能单体与配比。采用振荡平衡吸附实验对印迹和非印迹聚合物进行了吸附性能表征,结果表明,印迹聚合物对4种生物碱的饱和吸附量分别为7.53,10.90,24.27,11.04μg/mg,相对选择性系数分别为3.58,1.49,1.62,2.25。以该分子印迹聚合物为固相萃取柱填料,采用分子印迹固相萃取/高效液相色谱法实现了藏药马尿泡中4种托烷类生物碱的高效富集和快速分离。该方法在2~250μg/m L范围内具有较好的线性关系,相关系数(r2)为0.999 9,检出限为0.26~0.39μg/m L,在10,50,100μg/g加标浓度下的平均回收率为70.0%~96.3%,相对标准偏差(RSD)≤5.7%。该固相萃取柱重复使用率高,分离效果良好,有效去除了样品中杂质的干扰,大大提高了马尿泡果实中4种托烷类生物碱的萃取效率。     

分子印迹固相萃取/高效液相色谱法测定猪肝中盐酸克伦特罗的方法研究

建立了分子印迹固相萃取/高效液相色谱法测定猪肝中盐酸克伦特罗残留量的方法。以ASB C18色谱柱(250 mm×4.60 mm,5μm)分离,流动相为甲醇-水(45∶55,p H 3.0),紫外检测波长243 nm,进样量10μL,流速0.6 m L/min,柱温30℃。分子印迹固相萃取条件为:上样溶剂为双蒸水,上样流速为0.6 m L/min;洗脱剂为1%三氟乙酸的甲醇溶液。上述优化条件下,该方法在0.432~4.32μg/m L范围内线性关系良好,相关系数(r)为0.999 0。加标回收率为84.7%~92.0%,相对标准偏差(RSD)为1.5%~1.8%。方法的准确度和精密度满足残留分析的要求。     

分子印迹毛细管整体柱液相色谱法测定咖啡因

建立了一种新型高选择性分离测定咖啡因的微柱液相色谱法。在该方法中,以咖啡因为模板分子,经紫外光引发原位聚合制备了分子印迹毛细管整体柱。考察了柱制备过程中影响柱性能的主要因素,优化了色谱分离条件。结果显示所制备的分子印迹整体柱对咖啡因具有高度选择性,咖啡因与其结构相似物的最高分离度为2．57。将这一方法用于测定绿茶饮料、百事可乐和复方药片中咖啡因含量,获得满意结果。     

Determination of Acephate in Vegetables by Magnetic Molecularly Imprinted Polymer Isolation Coupled with High-Performance Liquid Chromatography

Magnetic molecularly imprinted polymers based on carbon nanotubes were prepared and characterized by infrared spectrometry, transmission electron microscopy, and vibrating sample magnetometry and were employed for the isolation of acephate from cabbage, spinach, lettuce, leeks, and celery. Kinetic and recognition studies were carried out in order to investigate the adsorption properties of the polymers. During the application process, the acephate extracted from vegetables was purified with the magnetic molecularly imprinted polymers and determined by high performance liquid chromatography with an ultraviolet detector. The recoveries of acephate at three fortified concentrations (0.015, 0.15, and 1.5 mg kg^?1) were between 89.2% and 93.4%. The limits of detection and quantification of acephate were 0.0025 and 0.0077 mg kg^?1, respectively. The linear dynamic range was from 0.01 to 5 mg kg^?1. The relative standard deviations of intra- and inter-day precision were 1.1% to 5.9% and 2.7% to 6.4%, respectively. The developed method was demonstrated to be rapid and selective for the extraction and determination of acephate in vegetables.     

分子印迹固相萃取-化学发光测定盐酸金霉素

分子印迹聚合物;固相萃取;化学发光;流动注射;金霉素     

固相萃取富集-高效液相色谱分离和测定邻甲苯胺和邻硝基甲苯

建立了以固相萃取技术进行富集 ,高效液相色谱进行分离和检测邻甲苯胺和邻硝基甲苯的方法。污染水中的邻甲苯胺和邻硝基甲苯采用Sep pakC1 8萃取柱进行固相萃取。色谱分离条件是 :Shim PackCLCODS(1 5 0mm× 4 .6mmid ,5 μm)柱为分析柱 ,甲醇 水 =60∶4 0 (V V)为流动相 ,流速为 1 .0mL min,邻甲苯胺和邻硝基甲苯的紫外检测波长分别为 2 3 0nm和 2 5 4nm ,本法具有良好的灵敏度和重现性。     

分子印迹磁固相萃取/气相色谱法分析环境水样中5种酰胺类除草剂残留

以丁草胺为假模板分子,丙烯酰胺为功能单体,利用四氧化三铁磁性纳米微球成功制备了具有特异性识别能力的磁性分子印迹聚合物。采用透射电子显微镜、红外光谱和振动样品磁强计对印迹聚合物进行表征,结果显示,分子印迹聚合物成功包裹在四氧化三铁表面。印迹聚合物对5种酰胺类除草剂均有特异性识别作用。以磁性分子印迹聚合物为基础,建立了酰胺类除草剂的气相色谱检测方法。方法学验证表明该方法具有良好的回收率(85.0%~99.5%)和精密度(RSD为2.8%~5.0%,n=5),线性范围为0.1~500μg·L~(-1),检出限为0.02~0.05μg·L~(-1)。该方法能够应用于农田灌溉用水等环境水样的测定。     

模板分子印迹聚合物磁性固相萃取-高效液相色谱法测定环境水样中四环素类抗生素

以介孔硅磁性氧化石墨烯为载体,四环素、土霉素、金霉素、强力霉素共同作为模板,N-［3-(三甲氧基甲硅烷基)丙基］乙二胺(KH-792)和苯胺甲基三乙氧基硅烷(KH-42)为功能单体,通过溶胶-凝胶法制备了四环素类抗生素多模板分子印迹聚合物。以扫描电镜(SEM)、红外光谱(IR)及振动样品磁强计(VSM)对聚合物进行表征。将所制备的多模板分子印迹聚合物作为吸附剂应用于磁性固相萃取,结合高效液相色谱法,建立了水样中四环素、土霉素、金霉素及强力霉素测定的新方法。该方法对4种四环素类抗生素的线性范围为5~50 μg/L,检出限为0.67~0.95 μg/L,定量下限为2.13~3.50 μg/L。实际样品的加标回收率为82.7%~103%,相对标准偏差(RSD)为1.0%~8.8%。方法可用于实际环境水样中4种四环素类抗生素的同时检测。     

Determination of Three Tanshinones from Radix Salvia Miltiorrhiza by Molecularly Imprinted Solid-phase Extraction

A selective molecularly imprinted solid‐phase extraction procedure was developed for the selective separation of tanshinone I, tanshinone IIA, and cryptotanshinone from Radix Salvia Miltiorrhiza samples. Tanshinone IIA imprinted polymers (MIP) synthesized in ethanol‐dodecanol system show high affinity to tanshinone IIA and its structure analogs in aqueous environment and the affinity can be controlled by adjusting the intensity of the eluents. By using 60% water‐40% methanol (volume ratio) and 99.5% methanol‐0.5% trifluoroacetic acid (volume ratio) as washing and eluting solvents, most interferences originating from the salvia matrix were eliminated. The extracts were sufficiently clean enough to be directly injected into HPLC for further chromatographic analysis. Good linearity was obtained from 0.4 to 500.0 mg·L^?1 (r²=0.999) with the relative standard deviations less than 4.2%. The mean recoveries of tanshinone IIA in Radix Salvia Miltiorrhiza were more than 85.6% at three different concentrations and the limits of detection were 0.06–0.09 mg·L^?1. This method is a viable alternative tool to the existing HPLC methods for analyzing the content of the three tanshinones in Radix Salvia Miltiorrhiza samples.