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采用沉淀聚合法制备了烟嘧磺隆(NS)分子印迹聚合物微球(NS-MIPMs)。以甲基丙烯酸(MAA)为功能单体、三甲氧基丙烷三甲基丙烯酸酯(TRIM)为交联剂、偶氮二异丁腈(AIBN)为引发剂、氯仿为致孔剂在60 ℃下加热引发聚合。对分子印迹微球的聚合工艺进行了优化,当NS/MAA/TRIM/AIBN的物质的量比为1:4:4:1、致孔剂体积为90 mL时,制备的NS-MIPMs的吸附能力最强。利用紫外分光光度计研究了模板分子和功能单体间的作用机理。结果表明,在预聚合阶段,功能单体和模板分子间的主要作用形式是一个模板分子与一个功能单体发生作用。通过静态吸附实验及动力学吸附研究考察了NS-MIPMs的吸附性能,并结合Scatchard模型分析得到聚合物的最大结合量为11370.5 μg/g。将制备的分子印迹微球应用于固相萃取技术中,制备烟嘧磺隆分子印迹固相萃取(NS-MIPMs SPE)小柱,并对小柱进行淋洗条件的优化。同时建立了NS-MISPE-HPLC快速检测土壤中烟嘧磺隆残留量的分析方法,样品中的农药经乙腈和磷酸盐缓冲液提取,提取液经NS-MIPMs SPE小柱净化后进行HPLC分析。结果表明,烟嘧磺隆在0.01~1 mg/L范围内线性关系良好,相关系数为0.9986;添加水平为0.02~1 mg/kg时的回收率为82.2%~86.3%,相对标准偏差为1.9%~4.3%。该方法简单、高效、重现性好,可用于土壤中烟嘧磺隆的快速检测。 相似文献
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In this work, the molecularly imprinted polymers (MIPs) and non-imprinted polymers (NIPs) for clopyralid (3,6-DCP) were successfully synthesized via precipitation polymerization using methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EGDMA) as crosslinker and a mixture of butanone (MEK) and n-heptane as porogen under the existence of azobisisobutyronitrile (AIBN). The morphologies, particle sizes, structures, adsorption properties and selective recognitions of polymers were investigated systematically. The average particle sizes of MIP3 and NIP3 were 2.76 μm and 2.15 μm. The apparent maximum binding amount (Qmax) of MIP3 and NIP3 were 67.50 mg·g?1 and 65.02 mg·g?1 in Scatchard analysis. Langmuir isotherm displayed that the Langmuir constant (Kl) of MIP3 and NIP3 were 0.015 L·mg?1 and 0.0065 L·mg?1, the saturation adsorption capacity (Qmax) of MIP3 and NIP3 were 63.23 mg·g?1 and 58.17 mg·g?1. Lagergren pseudo-second-order kinetic plot described that the adsorption process of MIP3 was visualized as chemical absorption. Selectivity analysis revealed that MIP3 possessed highly specific recognition for 3,6-DCP. 相似文献
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To obtain the desired specific adsorbents for carbaryl to enrichment, separation, and analysis of trace pesticide residues in environmental water, molecularly imprinted polymer (MIP) microspheres were prepared by precipitation polymerization using carbaryl, methacrylic acid (MAA), ethylene glycol dimethacrylate (EGDMA), azobisisobutyronitrile (AIBN), and acetonitrile as template, functional monomer, cross‐linker, initiator, and porogen, respectively. Molecular modeling software was used to compute rational interaction between the template molecule and function monomer. The adsorption properties of carbaryl in acetonitrile for imprinted microspheres were evaluated by equilibrium rebinding experiments. Scatchard plot analysis revealed that there was one class of binding sites populated in the imprinted polymer microspheres with dissociation constants of 3.3 × 10?2 mol/l and an apparent maximum number of 1.95 µmol/g. The specificity of the imprinted microspheres was investigated by binding analysis using carbaryl and structurally related carbamate pesticides. The results indicated that the obtained imprinted microspheres showed a good selectivity for carbaryl. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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以橄榄醇为模板分子,α-甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,甲苯和十二醇为溶剂,通过本体聚合法制备了橄榄醇分子印迹聚合物。利用平衡结合实验、扫描电镜(SEM)及红外光谱(FTIR)对分子印迹聚合物(MIP)进行了表征,并用该聚合物进行了加标麦麸中橄榄醇的固相萃取(SPE)研究。平衡结合实验表明MIP对模板分子具有更好的识别性。Scatchard分析表明对橄榄醇分子的吸附存在2类不同结合位点,其中高亲和力结合位点和低亲和力结合位点的解离常数分别为0.021和1.002 mmol/L,相应的最大表观结合量分别为18.74和135.9 μmol/g。在优化的固相萃取条件下,MIP固相萃取柱对加标麦麸中橄榄醇的回收率达到97.8%~98.8%,相对标准偏差为2.8%~4.2%(n=5),线性范围为0.1~100 mg/L,检出限(S/N=3)为0.062 mg/L。与非印迹聚合物(NIP)柱及市售聚苯乙烯/二乙烯基苯(PLS)柱相比,MIP柱的选择性更强,回收率更高,纯化效果更好。 相似文献
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《Journal of separation science》2017,40(4):971-978
Ordered macroporous molecularly imprinted polymers were prepared by a combination of the colloidal crystal templating method and the molecular imprinting technique by using SiO2 colloidal crystal as the macroporogen, quercetin as the imprinting template, acrylamide as the functional monomer, ethylene glycol dimethacrylate as the cross‐linker and tetrahydrofuran as the solvent. Scanning electron microscopy and Brunauer–Emmett–Teller measurements show that the ordered macroporous molecularly imprinted polymers have a more regular macroporous structure, a narrower pore distribution and a greater porosity compared with the traditional bulk molecularly imprinted polymers. The kinetic and isothermal adsorption behaviors of the polymers were investigated. The results indicate that the ordered macroporous molecularly imprinted polymers have a faster intraparticle mass transfer process and a higher adsorption capacity than the traditional bulk molecularly imprinted polymers. The ordered macroporous molecularly imprinted polymers were further employed as a sorbent for a solid‐phase extraction. The results show that the ordered macroporous molecularly imprinted polymers can effectively separate quercetin from the Gingko hydrolysate. 相似文献
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Molecularly imprinted microspheres (MIMs) were prepared by suspension polymerization for the binding and recognition of dibutyl phthalate (DBP). DBP was used as the template molecule, methacrylic acid as the functional monomer, ethylene dimethacrylate (EDMA) as the linking agent, PVA as the dispersing agent, and Span 60 as the surfactant. The MIMs were characterized with electron microscope scanning and rebinding experiments. The Scatchard plot revealed that the template‐polymer system has a two‐site binding behavior with dissociation constants of 4.05 and 0.515 mmol/L. The MIMs exhibited the highest selective rebinding to DBP at 736.85 μg/g. The recoveries of the MIM‐SPE column for DBP extraction was 94.75–101.9% with the RSD of 1.5–7.3%, indicating the feasibility of the prepared MIMs for DBP extraction. Finally, the method developed was used to analyze the trace levels of phthalate in aqueous environment samples. 相似文献
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Zhenhao Tong Yi Han Lili Gu Ziyi Li Kang Du Guanghui Kong Donghui Liu Jian Peng Junli Shi 《Journal of separation science》2020,43(6):1107-1118
This work provides a simple and rapid method for synthesis uniform simetryn imprinted nanoparticles, which can be used to pretreat the tested samples before detecting. A series of computational approach were employed for design simetryn‐imprinted polymer. Based on the conclusion of theoretical calculation, the simetryn imprinted nanoparticles were synthesized using simetryn as template, methacrylic acid as monomer with different solvent volume and synthesis conditions. The obtained nanoparticles have small size, uniform distribution and high imprinted factor. Scatchard analysis and quantum chemical calculations were applied for evaluating the interaction of simetryn with methacrylic acid in the imprinting process. The selectivity and recognition ability of the simetryn imprinted nanoparticles for six triazine herbicides and two other type herbicides were investigated. The results show that the simetryn imprinted nanoparticles had high selectivity and binding capacity and could be used for the separation and enrichment of four triazine pesticide residues from actual samples. A method of molecularly imprinted matrix solid phase extraction ultra‐performance liquid chromatography tandem mass spectrometry was established for detecting four kinds of triazine herbicide residues in tobacco. The recovery rate of terbuthylazine, simetryn, atrazine, and prometryn in tobacco was 84.03–119.05%, and the relative standard deviation was 0.35–10.12%. 相似文献
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Synthesis of molecularly imprinted polypyrrole as an adsorbent for solid‐phase extraction of warfarin from human plasma and urine 下载免费PDF全文
The aim of this work was to develop a method for the clean‐up and preconcentration of warfarin from biological sample employing a new molecularly imprinted polymer (MIP) as a selective adsorbent for solid‐phase extraction (SPE). This MIP was synthesized using warfarin as a template, pyrrole as a functional monomer and vinyl triethoxysilane as a cross‐linker. The molar ratio of 1:4:20 (template–functional monomer–cross‐linker) showed the best results. Nonimprinted polymers (NIPs) were prepared and treated with the same method, but in the absence of warfarin. The prepared polymer was characterized by Fourier transmission infrared spectrometry and scanning electron microscopy. An adsorption process (SPE) for the removal of warfarin using the fabricated MIPs and NIPs was evaluated under various conditions. Effective parameters on warfarin extraction, for example, type and volume of elution solvent, pH of sample solution, breakthrough volume and maximum loading capacity, were studied. The limits of detection were in the range of 0.0035–0.0050 µg mL?1. Linearity of the method was determined in the range of 0.0165–10.0000 µg mL?1 for plasma and 0.0115–10.0000 µg mL?1 for urine with coefficients of determination (R2) ranging from 0.9975 to 0.9985. The recoveries for plasma and urine samples were >95%. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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AbstractIn this research, hydrophilic molecularly imprinted microspheres (HMIPs) for azoxystrobin were successfully synthesized through precipitation polymerization. The adsorption capacities of HMIPs for azoxystrobin in water medium were higher than ordinary molecularly imprinted microspheres (MIPs), and HMIPs exhibited good hydrophilic properties. HMIPs and non-imprinted microspheres (HNIPs) were characterized by FT-IR, SEM, laser particle size analyzer and TGA. Comparing with HNIPs, azoxystrobin had a significant influence on morphologys and sizes of HMIPs. The Langmuir adsorption isotherm illustrated each binding site of HMIPs had the same adsorption capacity. The Lagergran pseudo-second-order kinetic model indicated the adsorption process between azoxystrobin and HMIPs was chemical adsorption. BET test illustrated HMIPs had bigger specific surface areas than HNIPs. Selective adsorption indicated that HMIPs had highly specific recognition of azoxystrobin. HMIPs successfully exhibited high selectivity and high hydrophilicity in water medium. 相似文献
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Primary creatine deficiency syndromes (CDS) are a new group of disorders caused by guanidinoacetate methyltransferase (GAMT) deficiency, which affects endogenous creatine biosynthesis with depletion of body creatine. A deficiency in creatine can be corrected by treatment with oral creatine supplementation and this necessitates a simple and sensitive screening method for early detection of creatine in dilute physiologic fluids. In this work an artificial receptor, molecularly imprinted polymer (MIP), for creatine was used both as a material for solid-phase extraction (SPE) and as a sensing element in a voltammetric sensor. Using the combination of molecularly imprinted solid-phase extraction (MISPE) with a complementary MIP sensor, the minimum detectable amount was found to be 0.0015 ng mL(-1) (RSD = 1.3%, S/N = 3). The MISPE-MIP sensor combination provided up to 60-fold preconcentration, which was more than sufficient for achieving the required quantification limit 50 ng mL(-1) (or 0.0025 ng mL(-1) after 2 x 10(4)-fold dilution) for creatine in human blood serum. 相似文献
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Xinyi Li Xiaolin Cao Zheng Zhang Ziping Zhang Zejun Jiang Jungang Yin 《Journal of separation science》2020,43(11):2133-2141
Molecularly imprinted polymers for strobilurin fungicides were prepared by precipitation polymerization employing azoxystrobin as template molecular together with methacrylic acid monomer and trimethylolpropane triacrylate cross‐linker. Morphological characterization showed molecularly imprinted polymers were uniform spherical particles with about 0.2 μm in diameter, while the morphologies of nonimprinted polymers were irregular bulk. The equilibrium binding and selective experiments proved that molecularly imprinted polymers possessed a higher affinity toward four fungicides compared to nonimprinted polymers and heterogeneous binding sites were found in the molecularly imprinted polymers. Molecularly imprinted solid‐phase extraction conditions, including sample loading solvents, selective washing, and elution solvents, were carefully optimized. The developed method showed good recoveries (70.0–114.0%) with relative standard deviations in range of 1.0–9.8% (n = 3) for samples (cucumber and peach) spiked at three different levels (10, 50, and 100 μg/ kg). The detection limit (signal/noise = 3) ranged from 0.01 to 0.08 μg/kg. The results demonstrated good potential use of this convenient and highly efficient method for determining trace strobilurin fungicides in agricultural products. 相似文献
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以吲哚美辛(IDM)为模板分子,丙烯酰胺(AA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,本体聚合法制备过程中加入纳米胶体金,合成了吲哚美辛胶体金分子印迹聚合物(MIPs/Au),利用MIPs/Au表面胶体金对蛋白吸附作用,将抗吲哚美辛的多克隆抗体固定在MIPs/Au上,得到表面固定有抗体的新型聚合物(MIPs/Au-Ab)并对其进行了表征。制备了填充材料为MIPs/Au-Ab的固相萃取柱并对其上样、淋洗和洗脱条件进行了优化,并将所制备的新型萃取柱用于水样中IDM的分离富集。抗吲哚美辛抗体交联在聚合物表面,不仅增加了萃取柱的特异性吸附容量,而且有效地降低了MIP的非特异性吸附。 相似文献
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Pengyan Liu Lei Liu Li Zhang Ning Jiang Zhanli Liu Yun Wang 《Frontiers of Chemistry in China》2008,3(4):378-383
A molecularly imprinted polymer (MIP), with special molecule recognition properties of ciprofloxacin (CIP), was prepared by
thermal polymerization in which ciprofloxacin acted as template molecule, α-methacrylic acid (MAA) acted as functional monomer and trimethylolpropane trimethylacrylate (TRIM) acted as crosslinker.
The optimized ratio was determined to be n(CIP): n (MMA):n(TRIM)51:6:16 by investigation of the effects of different concentrations of functional monomer and the crosslinker on the
MIP’s recognition properties. Equilibrium binding experiment was used to investigate the adsorption dynamics, the binding
ability to template molecule and the substrate selectivity. Scatchard analysis was used to study the MIP’s binding characteristic
to template molecule. The results indicated that MIP has higher adsorption ability and selectivity. The equilibrium distribution
coefficient K
D was 41.64 and the separation factor α was 1.62. Scatchard analysis showed that two different kinds of binding sites were produced in the polymer matrix and their
dissociation constants were calculated to be K
d1 = 5.249 × 10−5 mol·L−1, K
d2 = 2.237 × 10−3 mol·L−1.
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Translated from Chemistry, 2008, 71(2): 132–137 相似文献
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Molecularly imprinted microspheres (MIMs) were prepared by precipitation polymerization for the binding and recognition of 1,4-hydroxybenzoic acid esters. Ethyl p-hydroxybenzoate (EtPHB) was used as the template molecule, methacrylic acid as the functional monomer, ethylene dimethacrylate as the linking agent. It was evaluated by solid-phase extraction column packed with MIMs combined with liquid chromatography to determine trace preservatives including benzoic acid, methyl p-hydroxybenzoate, EtPHB, propyl p-hydroxybenzoate in food products. A solid-phase extraction based on MIM procedure was used to isolate four additives from the food matrix before quantitative analysis. The Scatchard plot suggested that the template-polymer system had two-site binding behavior with the dissociation constants of 0.3577 and 3.952 mg/g, respectively. The rebinding test, based on the molecularly imprinted solid-phase extraction column technique, showed the recoveries of soy samples spiked with four additives within 88.4-110.6%, with the relative standard deviations of 1.97-3.82%. Finally, the method was successfully applied for the analysis of parabens in foodstuff without traditional pretreatment. 相似文献