Study of the binding characteristics and transportation properties of a 4-aminopyridine imprinted polymer membrane

Molecularly imprinted polymer membranes containing artificial recognition sites for 4-aminopyridine have been prepared by photopolymerization using 4-aminopyridine as template. Reference membranes were prepared with the same monomer mixture but in the absence of the template. The binding characteristics of the imprinted polymer membrane were investigated by a batch method and the transport properties of the membranes were investigated using diffusion chambers. The results showed that the binding amount of 4-aminopyridine is higher than that of 2-aminopyridine whereas the latter can transport the ¶4-aminopyridine imprinted polymer membrane faster than 4-aminopyridine.     

4-氨基吡啶分子模板聚合物选择性识别及结合性质的研究

以4-氨基吡啶为模板分子制备了对4-氨基吡啶具有特异选择性的模板聚合物.制得的棒状聚合物经研磨、过筛后,采用平衡结合方法评价了该模板聚合物的结合特性.Scatchard分析表明,在所研究的浓度范围内,聚合物中形成了两类不同的结合位点,这两类结合位点的离解常数采用多点结合模型计算得到的值分别为6.0μmol/L和1.2mmol/L.底物选择性表明,与其它结构相似的分子相比,该聚合物对模板分子4-氨基吡啶显示了很强的结合能力.₁HNMR研究及4-氨基吡啶共振结构分析表明,模板分子与聚合物中的结合位点之间的作用为离子作用.     

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。     

钴离子配位分子印迹聚合物膜渗透特性的研究

采用分子印迹技术紫外光引发原位聚合的方法制备了带支撑膜的钴离子配位分子印迹聚合物膜. 用扫描电镜测定了膜的表面形貌. 通过膜渗透实验表明, 在一定浓度钴离子存在下, 印迹膜对模板分子表现出良好的渗透选择性. 分别考察了阳离子和阴离子对印迹膜渗透模板分子的影响. 本工作有助于分子印迹技术应用于传感器技术和连续分离技术的研究.     

白藜芦醇分子印迹复合膜的制备及其选择性能

以反式白藜芦醇为模板分子,聚偏氟乙烯微孔滤膜为支撑膜,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸脂(EDMA)为交联剂,采用热引发原位聚合方法制备了白藜芦醇分子印迹聚合物膜。研究了分子印迹膜对白藜芦醇及其结构类似物(2-萘酚、白藜芦醇甙和双酚A)的结合和透过性,并用扫描电镜对膜形貌进行了表征。结果表明,印迹复合膜对模板分子白藜芦醇具有良好的吸附选择性,印迹膜对白藜芦醇的吸附量远远大于其它结构类似物,其饱和吸附量达1.72μmol/g,为非印迹膜的3倍;尺寸效应和印迹效应是影响物质在印迹膜上的透过量的两个重要因素,尺寸比模板分子小的2-萘酚最先透过,而相对于尺寸接近或大于模板分子的双酚A或白藜芦醇甙,模板分子优先透过。而且,模板分子在印迹膜上的透过量大于非印迹膜。     

Evaluation of molecularly imprinted membranes based on different acrylic copolymers

Polyacrylonitrile and its copolymers with different functional monomers (itaconic acid, acrylic acid and acrylamide) were synthesized via water-phase precipitation polymerization in order to prepare molecularly imprinted polymer (MIP) membranes with recognition properties for the flavonoid naringin (NR). Membranes were prepared by phase inversion technique using dimethylformamide (DMF) as the solvent and adding naringin as template molecule to the casting solution. For comparison, membranes without template (blank) were prepared and tested. All MIP membranes showed high specific binding capacity; among them, the membrane prepared with the copolymer containing acrylamide as functional group, showed the highest binding capacity. Blank membranes only showed non-specific binding. The bound template was totally recovered and regenerated membranes maintained their initial binding capacity after reuse.     

锌-槲皮素配位分子印迹聚合物膜渗透特性的研究

采用紫外光引发原位聚合的方法制备了以聚偏氟乙烯管状微孔滤膜为支撑膜的锌离子配位分子印迹聚合物膜. 通过膜渗透实验表明, 在一定浓度锌离子存在下, 印迹膜对模板分子槲皮素表现出良好的渗透选择性. 分别考察了阳离子和阴离子对印迹膜渗透模板分子的影响. 本工作对分子印迹技术应用于实际样品中槲皮素的分离与富集具有重要意义.     

药物头孢氨苄分子模板聚合物水中结合性质的研究

采用分子模板技术合成了以头孢氨苄为模板分子以三氟甲基丙烯酸和４－乙烯基吡啶同时为功能单体的分子模板聚合物。将得到的棒状聚合物研磨过筛后,运用平衡结合实验研究了头孢氨苄分子模板聚合物的结合性质,Ｓｃａｔｃｈａｒｄ分析表明,在所研究的浓度范围内,在聚合物中形成了两类不同的结合位点。头孢氨苄分子模板聚合物与其化学组成相同的非模板聚合物相比,有很高的结合容量。底物选择性实验表明,与其它结构相似的药物相比,     

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。     

香豆素-3-羧酸分子印迹聚合物复合膜对底物的结合及渗透选择性质的研究

在光照和引发剂的作用下, 模板分子香豆素-3-羧酸、 功能单体丙烯酰胺和交联剂乙二醇二甲基丙烯酸酯(EDMA)或三甲氧基丙烷三甲基丙烯酸(TRIM)在聚偏氟乙烯(PVDF)微孔滤膜表面聚合形成分子印迹聚合物复合膜. 用高效液相色谱仪测定了分别以TRIM和EDMA为交联剂制备的分子印迹聚合物膜在不同溶剂中对混合底物的结合和渗透选择性. 结果表明, 以TRIM为交联剂的印迹膜对模板分子具有更高的结合和渗透选择性. 另外, 以乙腈或乙腈/水作为溶剂对分子印迹膜所作的实验和讨论有助于为从复杂样品中分离模板分子奠定理论和实验基础.     

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.     

Molecularly Imprinted Polymer with Calix[4]arene Derivative for the Recognition of Acetanilide

Two molecularly imprinted polymers binding to analgesic acetanilide were prepared using either dual functional monomers of calix[4]arene derivative and acrylamide or single monomer acrylamide, respectively. The polymers were ground, sieved and investigated by equilibrium binding experiment to evaluate their recognition properties for the template and other substrates. Scatchard analysis showed that homogeneous recognition sites were formed in the imprinted polymer matrix. Our results demonstrated that the polymer using two functional monomers exhibited better selectivity for the template. This study may open new frontiers for the development and application of imprinted polymers, such as drug separation and purification.     

Preparation and Cyclic Voltammetry Characterization of Cu—dipyridyl Imprinted Polymer

Polymer capable of specific binding to Cu-dipyridyl complex was prepared by molecular imprinting technology. The binding specificity of the polymer to the template (Cu-dipyridyl complex) was in vestigated by cyclic voltametric scanning using the carbon paste electrode modified by polymer particles in phosphate buffer solution. Factors that influence rebinding of the imprinted polymer were explored. The result demonstrated that the cycllic voltammetry was an efficient approach to explore interactions between template and imprinted polymers.     

伊诺沙星分子印迹聚合物的制备及分子识别性能研究

以伊诺沙星为印迹分子、甲基丙烯酸为功能单体、季戊四醇三丙烯酸酯为交联剂,合成了对伊诺沙星有较好选择性的印迹聚合物。利用铽敏化荧光,通过静态平衡结合法和Scatchard分析法研究了此印迹聚合物的结合能力和选择性,结果表明印迹聚合物对伊诺沙星有较高的亲和性和选择性。     

微球形4-氨基吡啶分子模板聚合物的合成及结合性质研究

利用分子印迹技术,通过沉淀聚合方法合成了对4-氨基吡啶具有选择性结合能力的微球形分子模板聚合物.通过静态结合方法研究了该聚合物的选择性结合能力以及不同溶剂及引发剂的用量对聚合物形态及球状聚合物粒径大小的影响.底物选择性实验结果表明,与结构相似的化合物相比,4-氨基吡啶球形分子模板聚合物对4-氨基吡啶显示出强的选择性.     

Molecularly imprinted polymer membranes for substance-selective solid-phase extraction from water by surface photo-grafting polymerization

Hydrophilized polyvinylidene fluoride microfiltration membranes were surface-modified in the presence of a template (terbumeton) in methanol with a graft copolymer of a functional monomer (2-acrylamido-2-methyl-1-propane sulfonic acid, AMPS, methacrylic acid, MAA, or acrylic acid, AA) and a cross-linker (N,N'-methylene-bis-acrylamide) using UV irradiation and benzophenone as photoinitiator. As result, membranes covered with a thin layer of imprinted polymer selective to terbumeton were obtained. Blank membranes were prepared with the same monomer composition, but in the absence of the template. The membranes' capacity to adsorb terbumetone from aqueous solution was evaluated yielding information regarding the effect of polymer synthesis (type and concentration of functional monomer, concentration of cross-linker) on the resulting membranes' recognition properties. UV spectroscopic studies of the interactions with terbumetone revealed that AMPS forms a stronger complex than MAA and AA. In agreement with that finding, imprinting with AMPS gave higher affinities than with MAA and AA. The terbumeton-imprinted membranes showed significantly higher sorption capability to this herbicide than to similar compounds (atrazine, desmetryn, metribuzine). With the novel surface modification technology, the low non-specific binding properties of the hydrophilized microfiltration membrane could successfully be combined with the receptor properties of molecular imprints, yielding substance-specific molecularly imprinted polymer composite membranes. The high affinity of these synthetic affinity membranes to triazine herbicides together with their straightforward and inexpensive preparation provides a good basis for the development of applications of imprinted polymers in separation processes such as solid-phase extraction.     

Selective separation of magnolol using molecularly imprinted membranes

Molecularly imprinted membranes (MIMs) for selective separation of magnolol were prepared by thermal polymerization using magnolol as the template, ethylene glycol dimethacrylate (EGDMA) as the cross‐linker, 2,2‐azobisisobutyronitrile (AIBN) as the initiator, organic solvent as the porogen, methacrylamide (MAM) and acrylic acid (AA) as the functional monomers and cellulose acetate as the agglutinant. Commercial filter paper was used as the supporting material. The effects of different porogens and the ratio of functional monomers on the binding and recognition capacity of MIMs were investigated, and the morphology of the membranes was examined by scanning electron microscopy (SEM). The results showed that the MIMs have the highest selectivity to magnolol when the ratio of MAM/AA was 1:4 and tetrahydrofuran (THF) with dimethyl sulfoxide (DMSO) was used as the porogen. The morphology of the imprinted membranes after template extracting is much rougher with big cavities than that of the non‐imprinted membranes (NIMs) and the imprinted membranes before template extracting. The MIMs can selectively separate the magnolol.     

Acrylonitrile-acrylic acid copolymer membrane imprinted with uric acid for clinical uses

The preparation of new polymeric membranes using molecular imprinting technology for application in blood filtration devices is described. Membranes, based on an acrylic acid-acrylonitrile copolymer, produced through phase inversion, were modified by introducing specific binding sites for uric acid into their structure. The materials prepared are intended for use to selectively remove uric acid from the blood in the case of increased serum uric acid values associated with different pathologies. The interactions at a molecular level between the membrane forming copolymer and the template were investigated by means of calorimetry, infrared spectroscopy and morphological analysis. The presence of interactions between the template and the copolymer, and a good thermal stability of the imprinted membranes were observed. In addition, the results of rebinding tests on the imprinted membranes indicated a good capacity of molecular recognition for the template and satisfactory selectivity properties towards compounds of similar structure such as theophylline. Membrane permeability values suggest their application as (ultra) haemofiltration devices. Poly(acrylonitrile-co-acrylic acid) membrane.     

Selective recognition of organic pollutants in aqueous solutions with composite imprinted membranes

In this work, thin-layer composite membranes imprinted with desmetryn or ibuprofen were prepared and studied for selective recognition of the template compounds in aqueous solutions. The imprinted membranes were developed using photoinitiated copolymerization of 2-acrylamido-2-methyl-1-propane sulphonic acid and N,N'-methylene-bis-acrylamide, in the presence of desmetryn or via copolymerization of dimethylaminoethyl methacrylate, and trimethylopropane trimethacrylate, in the presence of ibuprofen, followed by deposition of the imprinted layers on the surface of porous microfiltration supports of various chemical nature. Atomic force microscopy was used to study the surface morphological characteristics of the developed membranes. Molecularly recognition properties of imprinted membranes were evaluated by measuring their capability to bind the template molecules from polycomponent aqueous solutions. It was shown that obtained membranes may be used as selective recognising elements of portative differential capacitor sensor device for express monitoring of the target molecules in water. The sensor performance is based on registration of the alteration of dielectric permeability of composite imprinted membrane at selective binding of template molecules, when the analyzed feed solution is filtered through the membrane sample.     

药物甲氧苄氨嘧啶分子模板聚合物膜的选择性结合及透 过性质研究

用分子印迹技术制备了对甲氧苄氨嘧啶具有特异结合和透过性质的膜状分子模板聚合物,Scatchard分析表明,在分子模板聚合物膜中存在一类等价的可与甲氧苄氨嘧啶结合的位点,该结合位点的平衡离解常数为Kd=4.85×10^-2mmol/L,甲氧苄氨嘧啶分子模板聚合物膜的选择性透过实验表明,在该聚合物膜中存在着由形状和功能基团均与模板分子甲氧苄氨嘧啶相互补的孔穴组成的通道,该通道可有选择性地通过模板分子。