Imprinted microspheres doped with carbon nanotubes as novel electroresponsive drug‐delivery systems

Novel molecularly imprinted polymers (MIPs) suitable for the electroresponsive release of diclofenac were synthesized by precipitation polymerization in the presence of carbon nanotubes (CNTs). Both conventional and electroresponsive imprinted polymers were synthesized with methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. Preliminary experiments were performed to fully characterize the conventional MIPs and composite materials in terms of their morphological properties, recognition behavior, and electric resistivity. In vitro release experiments were performed in aqueous media to elucidate the ability of the MIPs and spherical imprinted polymers doped with CNTs to release the loaded template in a sustained manner over time in comparison to the that of the corresponding nonimprinted materials. Furthermore, a 20‐V direct‐current voltage was applied through the releasing media to evaluate how the electric field influenced the drug release to demonstrate the suitability of the proposed macromolecular system as an electroresponsive drug‐delivery device. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 829‐834, 2013     

Preparation of ordered macroporous cinchonine molecularly imprinted polymers and comparative study of their structure and binding properties with traditional bulk molecularly imprinted polymers

Three‐dimensionally ordered macroporous molecularly imprinted polymers (MMIPs) were prepared by a combination of the colloidal crystal template method and the molecular imprinting technique. Traditional bulk molecularly imprinted polymers (BMIPs) were simultaneously synthesized with the same recipe as the MMIPs by using methacrylic acid as functional monomer, ethylene glycol dimethacrylate as crosslinker and chloroform as porogen. SEM and Brunauer ? Emmett ? Teller measurements show that MMIPs have a more regular macroporous structure, a narrower macropore distribution and a greater surface area and porosity compared with BMIPs. The isothermal and kinetic data of both polymers can be fitted with the Freundlich model and a pseudo‐second‐order equation, respectively. Their specificities to the template molecules are also similar. However, the binding capability, adsorption rate coefficient and internal effective diffusion coefficient of the MMIPs are higher than for the BMIPs when the particle size is above 54 µm. © 2015 Society of Chemical Industry     

蛋白印迹膜洗脱方式的考察

选用丙烯酰胺作为功能单体,N,N’-亚甲基双丙烯酰胺为交联剂,制备牛血红蛋白的分子印迹聚合物。通过不同方法洗脱印迹膜,比较洗脱后印迹膜的洗脱率、吸附量以及选择性吸附效果。结果表明,酶洗脱的印迹膜具有较高的洗脱率,而通过醋酸和十二烷基硫酸钠洗脱的印迹膜对模板的吸附量和选择性却明显高于其它洗脱方法。     

Surface molecularly imprinted polymers based ZnO quantum dots as fluorescence sensors for detection of diethylhexyl phthalate with high sensitivity and selectivity

This work describes the preparation of molecularly imprinted polymers using ZnO quantum dots, which were used for the selective detection of diethylhexyl phthalate (DEHP). Methacrylic acid, ethylene glycol dimethacrylate, 2,2′‐azobis(2‐methylpropionitrile) and ZnO were used as functional monomer, crosslinker, initiator and optical material, respectively. Molecularly imprinted polymers were successfully synthesized, and the linear relationship between fluorescence intensity and amount was from 0.5 to 40 µmol L^?1 for DEHP. The coefficient of correlation was 0.9923 and the imprinting factor was 11.16. The results were above 97.50% and relative standard deviation below 3.86% for the detection of DEPH in actual water samples. This study could provide a novel method using molecularly imprinted polymers for highly selective and sensitive detection of DEHP. © 2018 Society of Chemical Industry     

沉淀聚合法制备烟酰胺分子印迹聚合物微球

以烟酰胺为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,乙腈为溶剂,采用沉淀聚合法制备了烟酰胺分子印迹聚合物,通过静态平衡吸附和色谱分析对印迹聚合物进行表征,结果表明,印迹聚合物对烟酰胺分子具有很好的吸附能力和特异识别性。     

基于壳聚糖的分子印迹聚合物的制备和应用

壳聚糖具有良好的生物相容性和独特的分子结构,基于其制备的分子印迹聚合物因亲和性和选择性高、应用范围广等特点引起了广泛的关注。本文首先总结了壳聚糖和改性壳聚糖在分子印迹聚合物制备中的作用,然后介绍了壳聚糖分子印迹聚合物在环境污染治理、医药、蛋白质分离与识别、手性物质分离以及吸附功能成分等方面的应用,分析了壳聚糖分子印迹聚合物在各个应用领域的优缺点及发展方向。最后,从发展绿色分子印迹技术以及分子印迹技术与电化学传感器结合等层面对壳聚糖分子印迹聚合物的应用前景进行了展望。     

单体对分子印迹聚合物分子识别能力的影响：量子化学计算与实验研究

采用密度泛函方法计算功能单体与印迹分子的结合能,以与目标分子结合能最大的单体分子来合成分子印迹聚合物.为此,以茶碱为印迹分子,氯仿为溶剂,首先计算了茶碱与甲基丙烯酸、丙烯酰胺和三氟甲基丙烯酸的结合能,其强度顺序为：三氟甲基丙烯酸 > 甲基丙烯酸 > 丙烯酰胺.然后以茶碱为印迹分子、氯仿为溶剂、二甲基丙烯酸乙二醇酯为交联剂,分别采用上述3种单体合成分子印迹聚合物并测定了其分子识别能力,实验结果和量子化学计算结果具有一致性.最后,采用1H NMR考察了茶碱和上述3种单体之间的氢键作用,揭示出二者相互作用的内在机制.研究结果表明量子计算方法可以应用于合成分子印迹聚合物时单体的选择.     

A new microemulsion approach for producing molecularly imprinted polymers with selective recognition cavities for gallic acid

Bulk and microemulsion systems were studied in order to obtain molecularly imprinted copolymers selective for gallic acid. Both systems contained acrylic acid as the functional monomer and ethylene glycol dimethacrylate as crosslinker. Microemulsion formation was confirmed by refractive index measurements and by conductivity analyses. Simple uptake tests revealed higher affinities for the microemulsion polymers; a 3.55 imprinting factor and a 0.275 g gallic acid (g polymer)^–1 adsorption capacity were recorded. Competitive uptake tests, from an oak bark extract, were in agreement with the simple uptake results and BET analyses. Microemulsion polymer particles selectively bind 4.58 times more gallic acid molecules relative to other competitor species.     

Synthesis of highly selective spherical caffeine imprinted polymers via ultrasound‐assisted precipitation polymerization

A facile and efficient method for synthesis of molecularly imprinted polymers via ultrasound‐assisted precipitation polymerization was developed. Caffeine was applied as a model template in the imprinting using methacrylic acid and ethylene glycol dimethacrylate as a functional monomer and a crosslinker, respectively. Polymerization under sonochemical conditions proceeded rapidly (within 3 h at 60°C) to afford polymer microspheres with narrow size distributions in excellent yields while maintaining the binding specificity toward the template. It was found that the imprinted polymer prepared at low initial temperature (40°C) exhibited the best caffeine binding performance in terms of specificity and selectivity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

硅胶表面罗丹明B分子印迹聚合物的制备及其性能研究

以表面接枝乙烯基的硅胶为载体,罗丹明B为模板分子,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸酯为交联剂,制备了表面印迹聚合物微球。通过静态吸附对吸附性能进行分析。结果表明,该印迹聚合物对模板分子具有特异吸附性能,并将其应用于固相萃取,测得罗丹明B的加标回收率为94.4%~101.2%,相对标准偏差(n=3)的范围为2.4%~3.4%。     

Preparation and characterization of magnetic molecularly imprinted polymers for selective recognition of 3‐methylindole

In this work, magnetic molecularly imprinted polymers (MMIPs) were used as novel adsorbents for selective adsorption of 3‐methylindole from model oil. The MMIPs were synthesized by precipitation polymerization and surface molecularly imprinted technique, using Fe₃O₄ nanoparticles as magnetically susceptible component, methylacrylic acid as dressing agent and functional monomer, ethylene glycol dimethacrylate as crosslinker, and 3‐methylindole as template molecule. The MMIPs were characterized by Fourier‐transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometer, and thermogravimetric analyzer, respectively. The adsorption performances of MMIPs were investigated by batch adsorption experiments in terms of kinetics, isotherms, and selective recognition adsorption, respectively. The results indicate that MMIPs have high recognition ability and fast binding kinetics for 3‐methylindole. Meanwhile, the adsorption equilibrium time was about 2 h and the equilibrium adsorption amount was ～38 mg g^?1 at 298 K. The heterogeneous MMIPs were modeled with pseudo‐second‐order and Langmuir isotherm equation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2859–2866, 2013     

Molecularly imprinted polymer microspheres prepared by precipitation polymerization using a sacrificial covalent bond

Molecularly imprinted polymer microspheres were prepared by precipitation polymerization using a sacrificial covalent bond. In the present model, cholesteryl (4‐vinyl)phenyl carbonate was used as a template monomer. The imprinted microspheres were prepared using ethylene glycol dimethacrylate (EDMA) and divinylbenzene (DVB) as crosslinker. The base‐labile carbonate ester bond was easily hydrolyzed to leave imprinted cavities in the resulting polymers. Radioligand binding analysis, elemental analysis, and scanning electron microscopy were used to characterize the imprinted materials. Imprinted microspheres prepared from DVB crosslinker had larger and more defined spherical shape, and displayed better imprinting effect than did the EDMA‐based microparticles. For comparison, imprinted bulk polymers were also prepared in the same reaction solvent as that used in precipitation polymerization. Elemental analysis results indicated that imprinted microspheres contained more template monomer units than bulk materials. The efficiency of template removal by hydrolysis treatment for microspheres was also higher than that for bulk polymers. For DVB‐based polymers, imprinted microspheres displayed higher specific cholesterol uptake than did the corresponding bulk polymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1390–1398, 2006     

Molecular dynamics simulations of molecularly imprinted polymer approaches to the preparation of selective materials to remove norfloxacin

A novel molecularly imprinted polymer (MIP) designed by molecular dynamics (MD) simulations was successfully prepared with norfloxacin as a template molecule, methyl acrylic acid as a functional monomer, and ethylene glycol dimethacrylate as a crosslinker. According to the theoretical prediction and experimental preparation methods, three kinds of molecular imprinting materials were designed and synthesized with MD simulations and molecular imprinting technology. The best ratio of the template to the functional monomer to the crosslinker was 1:8:40 in these studies. The experimental results illustrate that the MD simulations were credible in compounding the components of the MIPs. The structure of the prepared polymers were characterized with various methods. To analyze the adsorption performances, many kinds of static adsorption tests, including kinetic, isotherm, and selectivity tests, were used. The results indicate that the novel adsorbents conformed to the pseudo–second‐order kinetic equation and followed the Langmuir isotherm model. The adsorption amounts of MIP2 at a ratio of 1:8:40 were about 29.35 mg/g at 298 K_. The selective adsorption and reusable performance of norfloxacin were excellent. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 132, 42817.     

Preparation and evaluation of magnetic imprinted polymers for 2,4,6‐trinitrotoluene by surface imprinting

A safe and facile approach for the preparation of magnetic molecularly imprinted polymer nanospheres for 2,4,6‐trinitrotoluene (TNT) recognition is reported. The imprinted nanospheres were synthesized using TNT as the imprinting molecule, acrylamide as the functional monomer, N,N'‐methylenebisacrylamide as the crosslinker and magnetic particles as the support. The structure of the materials was identified via Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy and transmission electron microscopy. Static adsorbing experiments were carried out and Scatchard plot analysis showed that two kinds of receptor sites were formed in the imprinted materials. The adsorption equilibrium constant and the maximum adsorption capacity were evaluated. These results indicated that the imprinted nanospheres have higher adsorption capacity and selectivity for TNT than non‐imprinted polymer nanospheres with the same composition. © 2013 Society of Chemical Industry     

表面印迹聚合物的制备与吸附性能

以L-色氨酸作为模板分子,丙烯酰胺为功能单体,N,N'-亚甲基双丙烯酰胺为交联剂,通过在聚甲基丙烯酸甲酯多孔基质球表面复合印迹层,制备了L-色氨酸表面印迹聚合物微球(SMIPs),探索了不同比表面积基质球及添加丙烯腈对SMIPs吸附性能的影响,结果表明基质球比表面积为432.0m~2/g时,SMIPs对L-色氨酸的吸附量较高;当n(AN):n(L-trp):3:1时,SMIPs的综合吸附性能较好.     

Preparation and characterization of uniform molecularly imprinted polymer beads for separation of triazine herbicides

Uniform molecularly imprinted polymer beads were synthesized by precipitation polymerization for separation of triazine herbicides. A series of imprinted polymers were prepared using ametryn as template and divinylbenzene as crosslinking monomer, in combination with three different functional monomers under different solvent conditions. Under optimized reaction conditions, we obtained uniform molecularly imprinted polymer microspheres that display favorable molecular binding selectivity for triazine herbicides. The imprinted polymer beads synthesized using methacrylic acid as functional monomer in a mixture of methyl ethyl ketone and heptane showed the best results in terms of particle size distribution and molecular selectivity. Compared with nonimprinted polymer microspheres, the imprinted microspheres displayed significantly higher binding for a group of triazine herbicides including atrazine, simazine, propazine, ametryn, prometryn, and terbutryn. For the first time, precipitation polymerization has been used to produce highly uniform imprinted microspheres suitable for affinity separation of triazine herbicides. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

咖啡因分子印迹物的制备及其性能研究

采用分子印迹技术，以咖啡因为模板分子，丙烯酰胺为功能单体，二甲基丙烯酸乙二醇酯为交联剂，偶氮二异丁腈为引发剂，在氯仿中本体聚合方式制备了咖啡因分子印迹聚合物。紫外分光光度法对功能单体与模板分子之间聚合进行考察，结果表明，通过咖啡因分子印迹聚合物的制备，可实现咖啡因与结构类似物的分离和精制。     

Facile synthesis of magnetic molecularly imprinted polymers for caffeine via ultrasound-assisted precipitation polymerization

Facile method for preparation of magnetic molecularly imprinted polymers was developed via ultrasound-assisted precipitation polymerization using caffeine as the model template. Magnetic iron oxide powder was incorporated into the imprinted polymer matrix containing methacrylic acid and ethyleneglycol dimethacrylate as a functional monomer and a crosslinker, respectively. The amount of Fe₃O₄ and sonication time were varied and the recognition properties of the produced magnetic polymers were investigated. It was found that the developed method allow up to 41.4 % inclusion of iron oxide into the polymer beads in single step. Surface functionalization of the magnetic core and the use of additive surfactant or stabilizer were unnecessary. Under the optimum conditions, highly selective magnetic caffeine-imprinted polymer was produced in moderate yield with comparable recognition properties relative to the previously reported imprinted non-magnetic material.     

分子印迹聚合物与活性炭吸附性能的比较研究

以结晶紫为目标分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂制备出结晶紫分子印迹模板,研究了结晶紫分子印迹模板的吸附等温线、吸附量、吸附时间和作用位置,并与活性炭的吸附性能进行比较,结果表明,分子印迹模板的吸附量和吸附速度低于活性炭,但吸附的选择性高于活性炭。