以N-乙烯基吡咯烷酮为功能单体的S-萘普生印迹聚合物材料的合成及性能研究

以S-萘普生为模板,N-乙烯基吡咯烷酮为功能单体,二乙烯基苯为交联剂分别按照摩尔比1／4／10、1／4／20和1／4／30合成了分子印迹聚合物(MIP)。采用UV和Chem 3D Pro软件计算模拟研究了功能单体与模板分子之间的相互作用,经半经验量化PM3方法计算得到功能单体与模板分子之间的相互作用能为-20．97 kJ／mol。探讨了交联度对MIP吸附性能和识别能力的影响,结果表明在所研究的O～4mmol／L浓度范围内,MIP对S-萘普生的结合量随着交联度的增加而减小,而交联度为88％的印迹聚合物P3对S-萘普生和阿司匹林的分离因子为2．70,交联度为83％的聚合物P2的分离因子为2．60,交联度为71％的聚合物P1的分离因子为1.44,即高交联度MIP的识别能力优于低交联度的。     

1-氨基乙内酰脲分子印迹聚合物的制备和吸附性能研究

以1-氨基乙内酰脲(AHD)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,采用本体聚合方法合成了分子印迹聚合物(M IP),考察了模板分子与功能单体不同比例下制备的M IP对模板分子的吸附性能。通过Scatchard分析,表明该印迹聚合物上存在一类等价的吸附位点,其结合位点的离解常数KD=4.33mmol/L。     

Coatings of one monomer molecularly imprinted polymers for open tubular capillary electrochromatography

One monomer molecularly imprinted polymer coatings were first synthesized in fused silica capillary columns with 2-methacrylamidopropyl methacrylate (MAM) as single functional monomer in addition to a cross-linking monomer. Since MAM may generate no or little EOF, a strategy of precursor of polymerization, which does not interfere with the formation of defined imprints, was used to introduce an ionizable functional monomer to generate a stable electroosmotic flow for electrochromatography (CEC) by post-polymerization hydrolization. The resulting MAM-based open-tubular imprinted capillary was able to separate enantiomers by means of CEC. The resolution of enantiomers separation achieved on S-amlodipine-imprinted capillary was up to 16.1. The strong recognition ability (selectivity factor was 3.23) and high column performance (theory plates was 26,053 plates m(-1)) of template were obtained. The MIP coatings were also prepared using either S-naproxen or S-ketoprofen as template molecule. The resolutions of enantiomers separation were 2.20 and 4.56, respectively. The results illustrate that the synthesis of MIP using one monomer is not only an experimental-simplified process, but also an approach to producing chiral stationary phase with high efficiency and selectivity.     

分子印迹聚合物膜对氨基酸海因手性化合物的选择性结合和透过性质研究

合成了可对氨基酸海因对映异构体选择性分离的分子印迹聚合物膜。利用紫外光谱法比较不同功能单体与模板分子的作用能力。以丙烯酰胺为功能单体,在极性溶剂中制备了5R-5氨-基酸海因的分子印迹聚合物膜,通过Scatchard分析法研究膜中结合位点情况。通过膜透过实验研究印迹膜对外消旋体的分离特性。Scatchard分析显示聚合物膜中形成了两类结合位点,其解离常数分别为1.88mmol/L和5.14mmol/L;选择性透过实验表明膜中形成了与5R-5氨-基酸海因分子形状和功能基因位置匹配的孔穴。与非印迹聚合物膜相比,印迹聚合物膜对对映体具有良好的选择性。     

Comparison of three cross‐linking agents for imprinting diethylstilbestrol in solid‐phase extraction

Molecularly imprinted polymer (MIP) has been heavily studied for years. However, most efforts focused on functional monomer and particular study of cross‐linking agents on imprinting effect and pore structure is rare. In this paper, diethylstilbestrol (DES) imprinted polymers cross‐linked by three types of agents and their imprinting effects in solid‐phase extraction (SPE) were discussed. Evolution of UV spectral and simulation of cross‐linking agents or monomer mixed with DES revealed that there was a particular interaction between divinylbenzene and DES. Clear imprinting effects towards DES showed for divinylbenzene made imprinted polymer (DM), with imprinting factors up to 16.02 (STD = 2.20), while the other two imprinted polymers showed limited effects with imprinting factors of 4.95 (STD = 0.45) and 1.63 (STD = 0.54). Specific surface areas, pore volumes, and pore size distributions of the particles also confirmed that DM showed distinguished structure, and the average pore size of it was just fit the size of DES and bisphenol A (BPA), while no pore was found in divinylbenzene made blank polymer. Other imprinted and non‐imprinted polymers showed no pore or big pores relatively. These results show that the cross‐linking monomer is not merely an inert component for the MIPs, it could play a positive role in promoting interactions with the template to afford molecular recognition in imprinting DES. Copyright © 2011 John Wiley & Sons, Ltd.     

Preparation of “dummy” l‐phenylalanine molecularly imprinted microspheres by using ionic liquid as a template and functional monomer

In this study, dummy imprinting technology was employed for the preparation of l‐ phenylalanine‐imprinted microspheres. Ionic liquids were utilized as both a “dummy” template and functional monomer, and 4‐vinylpyridine and ethylene glycol dimethacrylate were used as the assistant monomer and cross‐linker, respectively, for preparing a surface‐imprinted polymer on poly(divinylbenzene) microspheres. By the results obtained by theoretical investigation, the interaction between the template and monomer complex was improved as compared with that between the template and the traditional l‐ phenylalanine‐imprinted polymer. The batch experiments indicated that the imprinting factor reached 2.5. Scatchard analysis demonstrated that the obtained “dummy” molecularly imprinted microspheres exhibited an affinity of 77.4 M·10^?4, significantly higher that of a traditional polymer directly prepared by l‐ phenylalanine, which is in agreement with theoretical results. Competitive adsorption experiments also showed that the molecularly imprinted polymer with the dummy template effectively isolated l‐ phenylalanine from l‐ histidine and l‐ tryptophan with separation factors of 5.68 and 2.68, respectively. All these results demonstrated that the polymerizable ionic liquid as the dummy template could enhance the affinity and selectivity of molecularly imprinted polymer, thereby promoting the development of imprinting technology for biomolecules.     

硅胶表面亮菌甲素分子印迹聚合物的制备及其性能研究

采用光接枝印迹方法,在硅胶微球表面制备了以亮菌甲素为模板分子、2-乙烯基吡啶为功能单体的分子印迹聚合物,采用荧光法优选了功能单体及比例,进一步用荧光法对印迹聚合物的吸附特性和印迹效率进行评价.结果表明.该印迹聚合物对模板分子具有特异吸附性能,印迹效率为48.6%.     

沉淀聚合制备诺氟沙星-Zn2+分子印迹聚合物及其印迹方式的研究

采用沉淀聚合的方式以诺氟沙星(NFA)-Zn2+为模板分子,乙二醇二甲基丙烯酸酯为交联剂,分别选取酸性功能单体甲基丙烯酸与碱性功能单体4-乙烯基吡啶制备了诺氟沙星-Zn2+的分子印迹聚合物.通过紫外光谱研究发现诺氟沙星与Zn2+及两种功能单体均发生了金属配位印迹作用且形成了比例不同的印迹复合物.红外光谱的功能基团的表征结果显示,甲基丙烯酸与诺氟沙星-Zn2+形成了以诱导作用占优的三元配合物,而4-乙烯基吡啶则与诺氟沙星-Zn2+形成了共轭作用占优的三元配合物.扫描电镜及粒径分布实验表征了聚合物的物理特性,结果显示印迹聚合物的表面存在孔及孔道结构而非印迹聚合物的表面较致密不存在孔且制备的印迹聚合物的粒径均在100μm以下,其平均粒径为39μm.等温结合及选择性实验的结果表明4-乙烯基吡啶为功能单体制备的印迹聚合物的选择性识别性能优于甲基丙烯酸为功能单体制备的印迹聚合物,其特异性吸附容量和印迹指数分别为66.84μmol/g和4.207.同时在混合溶液的选择性实验中以4-乙烯基吡啶(4-VP)为功能单体制备的印迹聚合物的选择识别诺氟沙星的能力优于以甲基丙烯酸为功能单体的聚合物,其识别因子分别为3.408和2.909,而非印迹聚合物对底物的吸附量较小且识别因子均接近于1,说明非印迹聚合物对底物的识别为非选择性的.     

Development and characterisation of a molecularly imprinted polymer prepared by precipitation polymerisation for the determination of phenylurea herbicides

New materials based on molecularly imprinted polymers (MIPs) have been developed for use as sorbents in solid phase extraction to preconcentrate some urea herbicides. In the preconcentration step, different molecularly imprinted polymers were tested using methacrylic acid (MAA) and 2-(trifluoromethyl)acrylic acid (TFMAA) as functional monomers, and linuron and isoproturon as templates. The best results were obtained when the polymer was synthesised using MAA with isoproturon as template. Another parameter evaluated was the way in which the polymer was obtained. We observed that the imprinted polymers obtained by precipitation displayed a greater capacity to retain the phenylureas. Studies conducted using scanning electron microscopy (SEM) revealed that the bulk polymerisation method is far from ideal owing to the random shape and size distribution of the particles obtained, whereas when polymerisation was carried out in precipitation microspheres were obtained. In order to confirm the interaction between the functional monomer and the template, 1H NMR (CD2Cl2) analyses were conducted. The results obtained suggest that the hydrogen and/or nitrogen of the amino group of the template would be involved in the formation of hydrogen bonds with the functional monomer. The imprinted polymer obtained by precipitation polymerisation with MAA as functional monomer and isoproturon as template can be applied to preconcentrate phenylureas when the sample is dissolved in toluene. The proposed methodology was employed to evaluate polymer selectivity towards humic acids and towards other herbicides.     

金属卟啉分子印迹聚合物的合成与性能研究

以5-(4-羟基苯基)-10,15,20-三苯基卟啉锌为印迹分子,4-乙烯基吡啶为功能单体,乙二醇二甲基丙烯酸酯为交联剂,合成了具有金属卟啉识别能力的分子印迹聚合物.紫外可见滴定光谱研究表明,功能单体与印迹分子在聚合前形成1:1的配合物.通过吸附试验、荧光光谱及斯卡查特分析法,考察了分子印迹聚合物对锌卟啉化合物的识别性能.结果表明,印迹聚合物对结构类似的卟啉化合物具有良好的识别能力,对印迹分子荧光性能的影响远大于其对应的非印迹聚合物.在浓度较低时,印迹聚合物对印迹分子的结合常数和最大结合量分别为:1.61×106L/mol和3.22×10-5mol/g.     

Enantiomeric Resolution on L—Carnitine Selective Polymers Prepared by Molecular Imprinting

L-carnitine selective polymers were prepared by molecular imprinting using methacrylic acid as the functional monomer. The acid function of the monomer is expected to form hydrogen bond and ionic interactions with the amine function of the target molecule L-carnitine.The imprinted polymers were used as stationary phases in high-performance liquid chromatography (HPLC). It was shown that L-carnitine imprinted polymer exhibited a higher affinity to its template molecule,while the non-imprinted polymer had no affinity to the compounds tested. Racemic carnitine hydrochloride was efficiently resolved on the L-carnitine imprinted polymer, and the separation factor is 1.9.     

环丙沙星分子印迹聚合物的合成及识别性能研究

采用分子印迹技术合成了以环丙沙星为印迹分子,以甲基丙烯酸和4-乙烯基吡啶同时为功能单体的分子印迹聚合物。运用平衡结合实验研究了印迹聚合物的吸附特性和选择识别能力。Scatchard分析表明,在所研究的浓度范围内,分子印迹聚合物中形成了两类不同的结合位点。底物选择实验表明,这种聚合物对环丙沙星呈现高的选择结合能力。     

内分泌干扰物雌酮分子印迹新型吸附功能材料的制备及其选择性能研究

采用分子印迹本体聚合法,制备了对内分泌干扰物雌酮具有高选择识别能力的分子印迹聚合物。吸附动力学和选择性实验结果表明,与非印迹聚合物相比,印迹聚合物具有较高的吸附容量和吸附速率,对模板分子具有较高的选择性。聚合反应条件对印迹聚合物的吸附和识别性能有重要影响,以丙烯酰胺为功能单体,模板分子、功能单体和交联剂摩尔比为1:3:6,制备的印迹聚合物具有较高的选择和吸附性能。     

Preparation, characterization and properties studies of quinine-imprinted polymer in the aqueous phase

The uniform-sized spherical molecularly imprinted polymers were successfully prepared through molecular imprinting technology by two-step seed swelling and mini-emulsion polymerization in the aqueous condition using quinine as template molecules and methacrylic acid (MAA) as functional monomer. The polymers were characterized by IR spectra, thermal-weight analysis, scanning electron microscope and laser particle size analysis. The properties of imprinted polymers were investigated in different organic phases and aqueous media. In the organic media, results suggested that polar interactions (hydrogen bonding, ionic interactions) between acidic monomer/polymer and template molecules are mainly responsible for the binding and recognition; whereas in the aqueous medium, a considerable recognition effect was also obtained where the ionic (electrostatic) interaction and hydrophobic interaction play an important role. The experiments of binding different substrates indicated that the MIPs possessed an excellent rebinding ability and inherent selectivity to quinine. __________ Translated from Zhongshan Dcocue Xuebao/Acta Scientianum Natralium University Sunyatseni, 2005, 44(3)(in Chinese)     

Sulfonamide imprinted polymers using co-functional monomers

Molecular imprinted polymers (MIPs) prepared using combination of acrylamide (ACM) and 4-vinylpyridine (4-Vpy) as co-functional monomers exhibited efficient recognition properties in both organic and aqueous media as HPLC stationary phase. The results indicate that amide and pyridine groups in functional monomers formed strong hydrogen-bonding interaction with the template molecule, and specific recognition sites were created within the polymer matrix during the imprinting process. When sulfamethoxazole (SMO) was used as template, a MIP prepared in a polar organic solvent (acetonitrile) using the combination of ACM and 4-Vpy showed better recognition of template than the polymer prepared in the same solvent using the combination of acidic monomer (methacrylic acid) and basic monomer 4-Vpy. On the contrary, when sulfamethazine (SMZ) was used as template, a MIP prepared using the combination of methacrylic acid (MAA) and 4-Vpy showed better recognition of template than the polymer prepared using the combination of ACM and 4-Vpy. Our results indicate that in organic media the degree of retention of the sample molecules on the imprinted polymers was controlled by the hydrogen-bonding interaction between the sample molecules and the polymer, while in aqueous media it was determined to a considerable extent by hydrophobic interactions. In both media the shape, size and the electronic structure of the template molecule were all-important factors in the recognition process.     

Influence of intramolecular hydrogen bond of templates on molecular recognition of molecularly imprinted polymers

Three molecularly imprinted polymers (MIPs) were prepared corresponding to three structurally related template compounds 4-hydroxybenzoic acid (4-HBA), gentisic acid (GA) and salicylic acid (SA) that differ in intramolecular hydrogen bonding ability using acrylamide (AA) as a functional monomer. HPLC method was used to evaluate the binding performances of the MIPs to the templates and several analogues. The results showed that the difference in their molecular recognition ability was pronounced. The highest molecular recognition ability was observed for 4-HBA-imprinted polymer. It was proved that the hydrogen bond interaction between the functional monomer and the template (4-HBA) played a major role in the recognition process and Scatchard analysis showed that two classes of binding sites were formed in 4-HBA-imprinted polymer. Their dissociation constants were estimated to be 1.76×10⁻⁴ and 1.40×10⁻³ mol l⁻¹, respectively. But for GA- or SA-imprinted polymer the molecular recognition ability was not improved compared to the blank polymer (BP). By comparison of the structures of the three templates, it was concluded that the molecular recognition ability will decrease when the template itself is able to form intramolecular hydrogen bond in the molecular imprinting process. This study will be helpful for us to understand the molecular recognition mechanism of MIPs and of instructive significance for the prediction of the selectivity of MIPs.     

二茂铁甲酸分子印迹聚合物的制备和识别机理、结合特性

以二茂铁甲酸（FCA）为模板,选用不同的功能单体制备了一系列分子印迹聚合物,用平衡结合实验考察了它们对模板分子的结合性能。 结果表明,以甲基丙烯酸为功能单体制得的印迹聚合物P1对模板分子有很好的选择性,特异性吸附量ΔCP为23.18 μmol/g,印迹因子IF为2.33,竞争性结合实验结果表明,P1可以将模板分子从结构类似物中分离出来。 Scatchard方程研究表明,在研究的浓度范围内聚合物中形成了一类等价的结合位点,其对模板分子的平衡离解常数K=1.94 mmol/L,最大表观结合量Cpmax=92.33 μmol/g。 研究还表明,FCA的羧基是在聚合物的孔穴中产生识别位点的功能基,模板分子上的羧基与MAA的羧基形成双重氢键作用是分子识别的主要作用力。     

扑热息痛分子印迹聚合物膜选择性结合和渗透性质的研究

采用紫外光引发原位聚合的方法制备了具有支撑膜的扑热息痛分子印迹聚合物膜. 紫外分光光度法证明了模板分子与功能单体之间存在相互作用, 并据此选择了聚合反应时合适的溶剂. 用傅立叶红外光谱和扫描电镜分别测定了膜的结构和表面形貌. 渗透实验结果表明渗透时所用溶剂对渗透结果有重要影响. 合适的渗透溶剂可提高印迹膜对模板分子的渗透选择性.     

A NOVEL MOLECULARLY IMPRINTED POLYMER： SYNTHESIS AND ADSORPTION BEHAVIOR OF GATIFLOXACIN

A kind of molecularly imprinted polymer （MIPs） with high selectivity was prepared using methacrylic acid （MAA） as functional monomer, ethylene glycol dimethacrylate （EDMA） as crosslinker and Gatifloxacin as template. The effect of various parameters such as volume of solvent, functional monomer dosage, crosslinker dosage and polymerization time were investigated. The selective binding experiment for substrates show that the affinity and selectivity for Gatifloxacin were higher than that for blank polymer. Scatchard analysis show that the MIPs recognized template with two kinds of binding sites. The dissociation constant Kd and maximum adsorption quantity Qmax of these two kinds of binding sites were calculated： Kd1 and Qmax1 of the binding sites with high affinity were 8.67×10^-4 mol/L and 28.19μmol/g, while Kd2 and Qmax2 of the binding sites with low affinity were 1.05×10^-3 mol/L and 33.20μmol/g respectively.     

Investigation of imprinting parameters and their recognition nature for quinine-molecularly imprinted polymers

A series of molecularly imprinted polymers (MIPs) was prepared using quinine as the template molecules by bulk polymerization. The presence of monomer-template solution complexes in non-covalent MIPs systems has been verified by both fluorescence and UV-vis spectrometric detection. The influence of different synthetic conditions (porogen, functional monomer, cross-linkers, initiation methods, monomer-template ratio, etc.) on recognition properties of the polymers was investigated. Scatchard analysis revealed that two classes of binding sites were formed in the imprinted polymer. The corresponding dissociation constants were estimated to be 45.00 micromol l(-1) and 1.42 mmol l(-1), respectively, by utilizing a multi-site recognition model. The binding characteristics of the imprinted polymers were explored in various solvents using equilibrium binding experiments. In the organic media, results suggested that polar interactions (hydrogen bonding, ionic interactions, etc.) between acidic monomer/polymer and template molecules were mainly responsible for the recognition, whereas in aqueous media, hydrophobic interactions had a remarkable non-specific contribution to the overall binding. The specificity of MIP was evaluated by rebinding the other structurally similar compounds. The results indicated that the imprinted polymers exhibited an excellent stereo-selectivity toward quinine.