壬基酚表面印迹聚合物微球的合成及分子识别特性

采用表面分子印迹技术,在二氧化硅微粒表面通过乙烯基三甲氧基硅烷接枝,以壬基酚(NP)为模板、α-甲基丙烯酸为功能单体制备了壬基酚印迹聚合物。扫描电镜及比表面分析仪测试结果表明制备的印迹聚合物呈均匀分散的微球,具有较大的比表面积。采用红外光谱表征印迹聚合物微球制备过程中的化学结构变化情况,并用平衡吸附法研究了聚合物对NP的结合性能与分子识别特性。研究结果表明,聚合物对壬基酚具有良好的结合亲和性,最大结合量可达184.6 mg/g。印迹聚合物对NP的吸附量高于其结构类似物对特辛基酚和双酚A的吸附量,表现出较高的选择性识别能力。     

铅离子印迹聚合物的制备、表征及其在水溶液中的吸附行为研究

以Pb2+为模板,壳聚糖为单体,硅胶为载体,γ-(2,3环氧丙氧)丙基三甲氧基硅烷(KH-560)为偶联剂,利用表面分子印迹技术和溶胶-凝胶法制备了Pb2+ 印迹聚合物.采用傅立叶变换红外光谱法(FT-IR)、紫外光谱法、扫描电镜对Pb2+ 印迹和非印迹聚合物的表面形貌和结构进行表征;并用电感耦合等离子体原子发射光谱法考察了吸附酸度、吸附剂用量、静置时间等对聚合物吸附性能的影响;研究了印迹聚合物在混合溶液中对Pb2+ 的选择性,比较了印迹和非印迹聚合物的吸附容量;并提出了印迹聚合物的印迹吸附机理.在最佳吸附酸度pH=4.5时,0.3 g 吸附剂吸附5 h达到平衡,Pb2+印迹聚合物对模板离子具有较高的选择性,其饱和吸附容量是非印迹聚合物的2倍.     

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%.     

手性药物(S)-布洛芬氢键自组装印迹聚合物识别机理

以含有单一结合基团的手性药物(S)-布洛芬作为模板分子,制备了系列印迹聚合物.采用紫外-可见光谱和红外光谱对印迹及识别机理进行了研究.结果表明,模板分子与功能单体分别通过形成蓝移氢键和红移氢键完成预组装过程和再识别吸附过程,且形成了主客体配比为1∶1的配合物.等温吸附实验结果表明,印迹聚合物对模板分子表现出明显的选择性吸附,特异性吸附容量为37.92μmol/g,印迹指数为3.06,且印迹聚合物内特定的三维空间结构对其特异性吸附性能具有显著影响.由手性分离实验考察了印迹聚合物的拆分性能,其对(R)-布洛芬的分离因子为1.79.     

溴代-1-甲基-3-己基咪唑离子液体表面分子印迹聚合物的制备及选择性吸附

以聚苯乙烯-二乙烯基苯颗粒为载体,制备溴代-1-甲基-3-己基咪唑离子液体表面印迹聚合物;通过扫描电镜、红外光谱、紫外光谱、比表面积及热分析等手段,对聚合物进行表征;静态实验结果显示,聚合物对模板底物有较强的吸附能力,印迹和非印迹聚合物对模板底物的饱和吸附量分别为667和322μmol g~(-1);动力学实验表明,印迹聚合物在1.0 h内能够达到吸附平衡,其吸附特征符合假二级动力学方程;选择性实验表明,印迹聚合物能够从结构类似物中选择性吸附模板分子。     

虚拟模板/硅胶表面分子印迹材料的制备及其在海水溶液中的吸附行为研究

以萘乙酸为虚拟模板,以甲基丙烯酸为功能单体、二甲基丙烯酸乙二醇酯为交联剂,用表面聚合-牺牲硅胶法合成了孔状结构的萘分子印迹聚合物.采用红外光谱、扫描电镜和N2吸附实验对印迹聚合物进行了表征;运用理论化学计算探讨了功能单体的筛选方法;利用平衡吸附法考察了印迹材料对海水中萘、蒽、菲化合物选择识别特性.实验表明: 以α-萘乙酸分子为模板的分子印迹聚合物对萘具有较好的识别能力.另外,由于α-萘乙酸分子中羧基的存在,使得分子印迹聚合物(MIP)的印迹空穴又与菲的体积大小相匹配,所以也表现出对菲的独特吸附能力.制备的印迹材料可望用于海水中2～3环多环芳烃的选择性吸附与富集.     

基于金属卟啉的分子印迹聚合物的合成及其对三唑类杀菌剂识别性能研究

以三唑类杀菌剂氟环唑为印迹分子,5-(4-甲基丙烯酰氧苯基)-10,15,20-三苯基卟啉锌为功能单体,乙二醇二甲基丙烯酸酯为交联剂,合成了新型的基于金属卟啉的分子印迹聚合物.紫外-可见光谱研究表明印迹分子与功能单体在聚合前形成1∶1配合物.通过选择性吸附和固相萃取表征研究了该印迹聚合物对氟环唑及具有类似化学结构的三唑类杀菌剂的识别能力,并与非印迹聚合物进行了比较,结果表明印迹聚合物具有良好的特异性识别性能,同时,印迹聚合物的交联度及吸附溶剂的极性对印迹效果有着显著影响.     

硅胶表面苯并噻吩分子印迹聚合物的分子识别与吸附性能

选用γ-氨丙基三乙氧基硅烷和α-甲基丙烯酸修饰的硅胶作为载体,以甲基丙烯酸为功能单体,二甲基丙烯酸乙二醇酯为交联剂,苯并噻吩为模板分子,合成一种具有选择性识别苯并噻吩分子的印迹聚合物。采用红外光谱、元素分析及N2吸附对其结构进行了表征,以模拟汽油通过静态吸附对其吸附性能进行了研究。结果表明,在硅胶载体表面成功地嫁接了多孔的分子印迹聚合物薄层。印迹聚合物对苯并噻吩具有良好的识别性能,对苯并噻吩的吸附动力学满足Langergren准一级反应动力学方程,吸附过程属于单分子层吸附。符合Langmuir吸附模型印迹聚合物对苯并噻吩的平衡吸附容量达57.4×10-3,而非印迹聚合物的吸附容量为33.1×10-3。印迹聚合物在经过多次再生后其吸附容量基本不变,从而为在汽油深度脱硫中有效脱除噻吩类硫化物提供了一种新技术途径。     

悬浮聚合法合成7-乙酰氧基-4-甲基香豆素分子印迹聚合物及其吸附性能研究

通过7-乙酰氧基-4-甲基香豆素作为黄曲霉毒素的替代模板合成分子印迹聚合物,使用紫外可见分光光度计测定聚合物对黄曲霉毒素的吸附,并进行合成条件优化。使用傅里叶变换红外、电子显微镜扫描、激光粒度分析仪对聚合物进行表征。对分子印迹聚合物进行吸附性能测试,得到分子印迹聚合物的最大吸附量为5.0 mg/g。将聚合物作为柱填料制备固相萃取柱检测黄曲霉毒素,并与免疫亲和柱对比,自制柱效果较好。     

发光性分子印迹聚合物的合成及其对组胺的识别性能研究

以组胺为模板分子,α-甲基丙烯酸为共功能单体,锌原卟啉为荧光功能单体,乙二醇二甲基丙烯酸酯为交联剂,合成了一种新的发光性分子印迹聚合物.通过振荡吸附后检测悬浊液荧光和柱吸附后检测流出液中组胺紫外光谱的变化,对印迹和非印迹聚合物与组胺的结合特性进行了对比.两种方法的结果一致,表明印迹聚合物对模板分子的识别选择性优于非印迹聚合物.     

Synthesis of molecularly imprinted polymer nanoparticles for the fast and highly selective adsorption of sunset yellow

Novel molecularly imprinted polymer nanoparticles were synthesized by precipitation polymerization with sunset yellow as the template and [2‐(methacryloyloxy)ethyl] trimethylammonium chloride as the functional monomer. The molecularly imprinted polymer nanoparticles were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and their specific surface area and thermal stability were measured. The molecularly imprinted polymer nanoparticles had a high adsorption capacity in wide pH range (pH 1–8) for sunset yellow. The adsorption equilibrium only needed 5 min, and the quantitative desorption was very fast (1 min) by using 10.0 mol/L HCl as the eluant. The maximum adsorption capacity of the molecularly imprinted polymer nanoparticles for sunset yellow was 144.6 mg/g. The adsorption isotherm and kinetic were well consistent with Langmuir adsorption model and pseudo‐second‐order kinetic model, respectively. The relative selectivity coefficients of the molecularly imprinted polymer nanoparticles for tartrazine and carmine were 9.766 and 12.64, respectively. The prepared molecularly imprinted polymer nanoparticles were repeatedly used and regenerated ten times without significant absorption capacity decrease.     

Highly selective separation and detection of cyromazine from seawater using graphene oxide based molecularly imprinted solid‐phase extraction

A novel molecularly imprinted polymer based on graphene oxide was prepared as a solid‐phase extraction adsorbent for the selective adsorption and extraction of cyromazine from seawater samples. The obtained graphene oxide molecularly imprinted polymer and non‐imprinted polymer were nanoparticles and characterized by scanning electron microscopy. The imprinted polymer showed higher adsorption capacity and better selectivity than non‐imprinted polymer, and the maximum adsorption capacity was 14.5 mg/g. The optimal washing and elution solvents for molecularly imprinted solid phase extraction procedure were 2 mL of acetonitrile/water (80:20, v/v) and methanol/acetic acid (70:30, v/v), respectively. The recoveries of cyromazine in the spiked seawater samples were in the range of 90.3–104.1%, and the relative standard deviation was <5% (n = 3) under the optimal procedure and detection conditions. The limit of detection of the proposed method was 0.7 μg/L, and the limit of quantitation was 2.3 μg/L. Moreover, the imprinted polymer could keep high adsorption capacity for cyromazine after being reused six times at least. Finally, the synthesized graphene oxide molecularly imprinted polymer was successfully used as a satisfied sorbent for high selectivity separation and detection of cyromazine from seawater coupled with high‐performance liquid chromatography.     

Synthesis of a molecularly imprinted polymer on mSiO2@Fe3O4 for the selective adsorption of atrazine

Atrazine contamination of water is of considerable concern because of the potential hazard to human health. In this study, a magnetic molecularly imprinted polymer for atrazine was prepared by the surface‐imprinting technique using Fe₃O₄ as the core, mesoporous silica as the carrier, atrazine as the template, and itaconic acid as the functional monomer. The magnetic molecularly imprinted polymer was characterized by Fourier‐transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, and vibration‐sample magnetometry. The binding properties of the magnetic molecularly imprinted polymer toward atrazine were investigated by adsorption isotherms, kinetics, and competitive adsorption. It was found that the adsorption equilibrium was achieved within 2 h, the maximum adsorption capacity of atrazine was 8.8 μmol/g, and the adsorption process could be well described by the Langmuir isotherm model and pseudo‐second‐order kinetic model. The magnetic molecularly imprinted polymer exhibited good adsorption selectivity for atrazine with respect to structural analogues, such as cyanazine, simetryne, and prometryn. The reusability of the magnetic molecularly imprinted polymer was demonstrated for at least five repeated cycles without a significant decrease in adsorption capacity. These results suggested that the magnetic molecularly imprinted polymer could be used as an efficient material for the selective adsorption and removal of atrazine from water samples.     

Preparation of magnetic molecularly imprinted polymer nanoparticles by surface imprinting by a sol–gel process for the selective and rapid removal of di‐(2‐ethylhexyl) phthalate from aqueous solution

Magnetic molecularly imprinted polymer nanoparticles for di‐(2‐ethylhexyl) phthalate were synthesized by surface imprinting technology with a sol–gel process and used for the selective and rapid adsorption and removal of di‐(2‐ethylhexyl) phthalate from aqueous solution. The prepared magnetic molecularly imprinted polymer nanoparticles were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and vibrating sample magnetometry. The adsorption of di‐(2‐ethylhexyl) phthalate onto the magnetic molecularly imprinted polymer was spontaneous and endothermic. The adsorption equilibrium was achieved within 1 h, the maximum adsorption capacity was 30.7 mg/g, and the adsorption process could be well described by Langmuir isotherm model and pseudo‐second‐order kinetic model. The magnetic molecularly imprinted polymer displayed a good adsorption selectivity for di‐(2‐ethylhexyl) phthalate with respect to dibutyl phthalate and di‐n‐octyl phthalate. The reusability of magnetic molecularly imprinted polymer was demonstrated for at least eight repeated cycles without significant loss in adsorption capacity. The adsorption efficiencies of the magnetic molecularly imprinted polymer toward di‐(2‐ethylhexyl) phthalate in real water samples were in the range of 98–100%. These results indicated that the prepared adsorbent could be used as an efficient and cost‐effective material for the removal of di‐(2‐ethylhexyl) phthalate from environmental water samples.     

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。     

Recognition of Staphylococcus enterotoxin via molecularly imprinted beads

The synthesis of molecularly imprinted beads for the recognition of the protein Staphylococcus enterotoxin B (SEB) is described. Two kinds of organic silane (3-aminopropyltrimethoxysilane (APTMS) and octyltrimethoxysilane (OTMS)) were polymerized on the surface of polystyrene microspheres after the SEB template was covalently immobilized by forming imine bonds. The resulting imprinted beads were selective for SEB. The Langmuir adsorption models were applied to describe the equilibrium isotherms. The results showed that an equal class of adsorption was formed in the molecularly imprinted polymer (MIP) with the maximum adsorption capacity of 3.86 mg SEB/g imprinted beads. The MIP has much higher adsorption capacity for SEB than the nonimprinted polymer, and the MIP beads have a higher selectivity for the template molecule.     

Synthesis and Adsorption Performance of Surface‐Grafted Co(II)‐Imprinted Polymer for Selective Removal of Cobalt

The surface‐grafting ion‐imprinting technology was applied to synthesis of a new Co(II)‐imprinted polymer [Co(II)‐IP], which could be used for selective removal of Co(II) from aqueous solutions. The prepared polymer was characterized by using the infrared spectra (IR), X‐ray diffractometer (XRD), X‐ray energy dispersion spectroscopy (EDS) and scanning electron microscopy (SEM). The maximum adsorption capacity values for the Co(II)‐imprinted polymer and non‐imprinted polymer (NIP) were 22 and 8 mg/g, respectively. The Freundlich equation fitted the adsorption isotherm data well. The applicability of two kinetic models including pseudo‐first‐order and pseudo‐second‐order models was estimated on the basis of comparative analysis of the corresponding rate parameters, equilibrium capacity, and correlation coefficients. Results suggested that chemical process could be the rate‐limiting step in the adsorption process. And the adsorption of Co(II) on the Co(II)‐imprinted polymer was endothermic. The relative selectivity coefficients of the Co(II)‐imprinted polymer for Co(II)/Pb(II), Co(II)/Cu(II), Co(II)/Ni(II), Co(II)/Sr(II) and Co(II)/Cs(I) were respectively 11.5, 6.1, 13.8, 9.4, and 8.1 times greater than that of the non‐imprinted polymer. Eventually, the desorption conditions of the adsorbed Co(II) from the Co(II)‐imprinted polymer were also studied in batch experiments.     

Molecularly imprinted polymer coating on metal‐organic frameworks for solid‐phase extraction of fluoroquinolones from water

In this work, a novel surface molecularly imprinted polymer with high adsorption capacity, high adsorption rate, and high selectivity for fluoroquinolones was prepared on the surface of UiO‐66‐NH₂, which is a kind of metal‐organic framework. The surface morphology and adsorption properties of this molecularly imprinted polymer were investigated. The maximum adsorption capacity was 99.19 mg/g, and adsorption equilibrium was achieved within 65 s. Combined with reversed‐phase high‐performance liquid chromatography, the molecularly imprinted polymer was used to selectively enrich, separate and analyze fluoroquinolones present in lake water. The results showed that the recoveries of the four fluoroquinolones were 92.6–100.5%, and the relative standard deviations were 2.9–6.4% (n = 3). The novel molecularly imprinted polymer is an excellent adsorbent and has broad application prospects in the enrichment and separation of trace analytes in complex samples.     

Tailor‐made ion‐imprinted polymer based on functionalized graphene oxide for the preconcentration and determination of trace copper in food samples

A tailor‐made Cu(II) ion‐imprinted polymer based on large‐surface‐area graphene oxide sheets has been synthesized for the preconcentration and determination of trace copper from food samples by solid‐phase extraction. Attributed to the ultrahigh surface area and hydrophilicity of graphene oxide, the Cu(II) ion‐imprinted polymer prepared by the surface ion‐imprinting technique exhibited a high binding capacity and a fast adsorption rate under the optimized experimental conditions. In the static adsorption experiments, the maximum adsorption capacity of Cu(II) ion‐imprinted polymer is 109.38 mg/g at 25°C, which is much higher than that of the nonimprinted polymer (32.12 mg/g). Meanwhile, the adsorption is very rapid and equilibrium is reached after approximately 30 min. The adsorption mechanism is found to follow Langmuir adsorption model and the pseudo‐second‐order adsorption process. The Cu(II) ion‐imprinted polymer was used for extracting and detecting Cu(II) in food samples combined with graphite flame atomic adsorption spectrometry with high recoveries in the range of 97.6–103.3%. The relative standard deviation and limit of detection of the method were evaluated as 1.2% and 0.37 μg/L, respectively. The results showed that the novel absorbent can be utilized as an effective material for the selective enrichment and determination of Cu(II) from food samples.