谷胱甘肽分子印迹聚合物的制备及其性能研究

采用新型光源高压汞灯制备了三肽分子谷胱甘肽的分子印迹聚合物(MIPs), 反应时间缩短, 制备条件温和. 对MIPs做了一系列的静态吸附实验, 结合荧光测定法研究了不同单体-模板比例下MIPs表现出来的吸附性能. 对最佳比例制备的MIPs进行了一系列性能研究, 包括吸附等温线的测定、Scatchard分析以及薄层色谱分离实验等. 结果表明, 所合成的MIPs对GSH具有良好的吸附和选择识别能力,最大吸附量为45.4 mg/g, 特异因子达到了4.98.     

磺胺二甲氧嗪印迹材料的制备及性能表征

以磺胺二甲氧嗪(SDM')为模板分子,丙烯酰胺(AM)为功能单体,在乙腈中采用沉淀聚合法制备MIPs,并在优化条件下,对吸附性能进行了表征。静态吸附表明,MIPs的吸附量是NIPs的2.08倍,Scatchard分析表明MIPs与SDM'之间存在一种结合位点;动态吸附实验、粒子扩散模型和Elovich模型表明吸附过程存在两种吸附模式,且属自发的化学吸附过程;选择性实验显示,MIPs对SDM'具有优异的专一识别性能。     

有机磷神经毒剂分子印迹聚合物的模拟模板分子

采用DFT/B3LYP-D3(BJ)/6-31G(d,p)计算模拟方法分析探讨了双(对硝基苯基)磷酸酯(BNPP)替代对氧磷(PO)用作有机磷神经毒剂分子印迹聚合物(MIPs)模板分子模拟物的可行性. 通过对比BNPP和PO两种模板分子分别与各种功能单体形成的复合物的构型稳定性和结合能大小, 确认了以4-甲基丙烯酰胺基安替比林(MAAP)为第一功能单体、 甲基丙烯酸(MAA)为第二功能单体组成的双功能单体体系是最佳功能单体体系. 以BNPP为模板分子、 MAAP-MAA为单体体系、 乙二醇二甲基丙烯酸酯(EGDMA)为交联剂、 纳米二氧化硅为载体, 采用表面印迹技术制备了SiO₂@BNPP分子印迹聚合物, 并对聚合物的表面形貌和吸附性能进行了分析. 实验结果表明, 当n(BNPP)/n(MAAP)/n(MAA)/n(EGDMA)为1∶1∶4∶20时, MIPs的吸附容量最大可达19.03 mg/g, 对4-硝基苯酚(4-NP)的分离因子为17.50; MIPs能够快速吸附模板分子, 5 min即可达到吸附平衡量的92%, 动态吸附平衡时间仅为15 min, 重复使用5次后仍能保持良好的吸附能力; 吸附过程符合准二级动力学模型和Langmuir等温吸附模型, Scatchard方程分析表明MIPs中存在两类吸附作用位点. 实验结果与计算模拟结果的一致性表明, 计算模拟对有机磷神经毒剂MIPs的设计和研究具有一定的指导意义.     

单分散的二氧化硅微球表面印迹壳层的制备及其对食品包装材料中邻苯二甲酸二苄酯的检测

以邻苯二甲酸二苄酯(DBz P)为模板,以Stber和"种子生长法"相结合获得的二氧化硅微球为载体,采用表面印迹技术成功制备了纳米印迹壳层(MIPs)。采用红外光谱与扫描电镜对其结构和形貌进行表征,同时进行了一系列的吸附性能实验,结果表明,MIPs达到平衡吸附的时间约为30 min,吸附行为符合伪二级动力学。等温吸附实验结果表明,室温条件下MIPs的最大吸附量达47.35 mg/g。对不同温度条件下的等温实验数据进行拟合发现,Langmuir模型与实验数据的吻合度比Freundlich模型更高;Scatchard拟合结果证实该印迹壳层仅含1种结合位点,且印迹位点为均相分布。选择性吸附实验表明MIPs对DBz P的吸附明显高于其他结构类似物。MIPs经10次循环吸附后,吸附效率为83%,表明MIPs具有较长的使用寿命。采用超高效液相色谱(UPLC)技术,以MIPs为吸附剂提取食品包装材料中的DBzP,其加标回收率为88.8%~93.1%,相对标准偏差低于6%。MIPs可作为食品及其包装材料中DBz P提取的备选材料。     

琥乙红霉素分子印迹聚合物微球的制备及表征

以琥乙红霉素为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,采用悬浮聚合法制备得到了平均粒径约为60μm的琥乙红霉素分子印迹聚合物微球(MIPs),并用扫描电镜对其表面形貌进行了表征。考察了琥乙红霉素分子印迹聚合物的印迹效果,研究了琥乙红霉素分子印迹聚合物的动力学吸附特性。比较了MIPs对琥乙红霉素及其它3种抗生素的吸附情况。结果表明,制备得到的琥乙红霉素分子印迹聚合物微球对琥乙红霉素具有最好的吸附能力,显示出MIPs具有高的选择性。     

环丙沙星与三氟甲基丙烯酸分子印迹自组装体系的理论研究

采用量子化学长程校正方法, 以环丙沙星(CIP)为印迹分子, 三氟甲基丙烯酸(TFMAA)为功能单体, 研究了CIP与TFMAA单体分子印迹聚合物(MIPs)自组装体系的构型、 成键作用位点、 反应的结合能、 作用机理及其选择性. 计算结果表明, CIP印迹分子与TFMAA单体通过氢键形成分子结构互补的有序排列复合物, 当印迹分子与功能单体配比(印迹比例)为1: 6时, 其复合物能量最低; 通过模拟洗脱CIP后的复合物对恩诺沙星(ENR)、 诺氟沙星(NOR)、 氧氟沙星(OFL)再结合的结合能可以预测MIPs对CIP印迹分子的选择性, CIP与OFL共存时MIPs对CIP的选择性最好. 采用不同印迹比例, 测定聚合物对CIP的吸附量, 结果表明, 印迹比例为1: 6时, 聚合物吸附量最大, 且对OFL的选择因子最大, 实验结果与计算结果一致.     

硅胶表面苏丹红1分子印迹聚合物的制备与性能考察

本文以硅胶为载体,γ-(甲基丙烯酰氧基)丙基三甲氧基硅烷为表面修饰分子,苏丹红1为模板分子,2-乙烯吡啶为功能单体,N,N-亚甲基双丙烯酰胺为交联剂,偶氮二异丁腈为引发剂,制备了硅胶表面修饰分子印迹聚合物(MIPs)。红外光谱(FT-IR)验证了MIPs的成功制备,扫描电子显微镜(SEM)观察了MIPs的表面形貌,通过静态平衡吸附法考察了印迹材料的吸附动力学和饱和吸附量,并通过竞争性吸附对MIPs的吸附选择性进行了分析。     

正丁醇分子印迹聚合物的制备及其吸附性能

以正丁醇为模板分子,采用本体聚合法制备了正丁醇分子印迹聚合物。利用扫描电镜和红外光谱对该聚合物进行表征,并利用动态吸附、静态吸附和选择性吸附实验评价其吸附性能。正丁醇分子印迹聚合物能够特异性识别正丁醇,通过计算得到正丁醇MIPs的分离因子α为2.057,印迹因子IF为2.123。此聚合物制备简单、可重复利用并且表现出良好的选择性,可作为固相萃取填料应用于食品中正丁醇的分离、富集和检测。     

磁性双酚A分子印迹材料的制备及性能研究

采用沉淀法制备了Fe_3O_4磁性微球,以硅烷化试剂对其表面改性后作为载体,以双酚A为模板分子,甲基丙烯酸为功能单体,N,N′-亚甲基双丙烯酰胺为交联剂,采用乳液聚合法制备了对BPA有特异吸附性能的磁性分子印迹材料(MMIPs)。此材料具有较强的磁性和对双酚A的吸附性,可以在外加磁场的条件下方便实现水中双酚A的富集分离。溶液中双酚A的质量浓度为60mg·L~(-1)时,制备的磁性MIPs材料对双酚A饱和吸附量为22.06mg·g~(-1),60min达到吸附平衡。     

鞣花酸分子印迹聚合物的合成及其性能研究

以鞣花酸为模板分子,4-乙烯基吡啶(4-VP)为功能单体,二甲基丙烯酸乙二醇酯(EDMA)为交联剂,通过沉淀聚合法合成鞣花酸(EA)分子印迹聚合物(MIPs).采用红外光谱、比表面积测定、扫描电镜、静态吸附试验、选择性吸附试验对其结构和性能进行表征.结果表明:最佳制备条件为聚合温度65℃,以70 mL二甲基亚砜为致孔剂...     

分子印迹聚合物吸附性能的影响因素探讨

分子印迹聚合物具有对特定分子的亲和性和高选择性,稳定性好、使用寿命长、应用范围广等特点,因此在很多领域,如色谱分离[1]、固相萃取[2]、仿生传感[3]、模拟酶催化[4]、临床药物分析[5]、膜分离[6]等得到日益广泛的研究和应用。影响分子印迹聚合物与模板分子之间识别作用的因     

芦丁-槲皮素双模板印迹聚合物的制备、表征及识别

以芦丁(RT)-槲皮素(QT)为混合模板分子制备了芦丁-槲皮素复合模板分子印迹聚合物。 优化了制备条件,研究了模板用量比、功能单体及交联剂用量对印迹聚合物吸附性能的影响。 用傅里叶红外光谱和扫描电镜对分子印迹聚合物进行结构表征。 探讨了分子印迹聚合物的吸附动力学、等温吸附及键合位点特征,考察了其选择识别性能,并以分子印迹聚合物为吸附介质,萃取分离芦丁粗提液中的目标化合物。 结果表明,当槲皮素与芦丁的摩尔比为3:2,且模板总量与功能单体及交联剂用量摩尔比为1:8:10时,所得分子印迹聚合物的吸附性能最好,对槲皮素和芦丁的吸附量分别达47.86和60.97 mg/g。 吸附可在3.5 h内达到平衡,显示了较快的吸附动力学。 Scatchard分析表明,分子印迹聚合物基体中存在四类不同性能的键合位点,分别为芦丁和槲皮素的高亲和键合位点及非选择键合位点。 相对分布系数(k=K_d(RT)/K_d(QT),K_d=q_e/ρ_e,K_d为分布系数,q_e为平衡吸附量,ρ_e为平衡质量浓度)大于1,表明了分子印迹聚合物对芦丁具有更高的选择键合作用,当模拟混合物中芦丁和槲皮素浓度分别为0.07和0.03 mmol/L时,相对分布系数和分离因子(α=q_e(RT)/q_e(QT))分别达6.669和25.02。 另外,以乙腈、甲醇及甲醇-醋酸混合物依次为洗脱剂,通过分子印迹固相萃取可从槐米提取物中分离芦丁和槲皮素两种黄酮类化合物,总回收率分别为96.70%和94.67%。     

双甘氨肽分子印迹聚合物微球的吸附性能研究

以双甘氨肽(Gly-Gly)为印迹分子,丙烯酰胺(AM)、二甲基丙烯酸乙二醇酯(EDMA)分别作为功能单体和交联剂,在低温条件下采用乳液聚合于水相中制备了双甘氨肽分子印迹聚合物微球(Gly-Gly-MIPMs)。通过静态、动态平衡吸附和薄层色谱(TLC)分离实验,研究了Gly-Gly-MIPMs的选择吸附性能,并进行了Scatchard模型分析。结果表明,Gly-Gly-MIPMs对Gly-Gly分子具有较好的特异性吸附,最大单位饱和吸附量0.428mmol/g,印迹因子2.19。     

Towards ochratoxin A selective molecularly imprinted polymers for solid-phase extraction

Molecularly imprinted polymers (MIPs) displaying selective binding properties for the mycotoxin ochratoxin A (OTA) in polar/protic media were prepared. Crucial to the success of these efforts was the implementation of rationally designed OTA mimics as templates and a set of novel basic and neutral functional monomers, allowing the maximization of the template-functional monomer association via ion-pairing, hydrophobic and steric interactions. MIPs prepared with a 20:1:1:3 molar ratio of cross-linking agent, template mimic, basic functional monomer and hydrophobic auxiliary monomer produced polymers with superior recognition properties compared to materials generated with other stoichiometries. Chromatographic evaluation using the OTA mimics, OTA and a set of structurally closely related compounds as analytes revealed pronounced substrate selectivity of these MIPs in polar/protic media, the templates and OTA being bound with significantly higher affinities. Complementary substrate selectivities/affinities were observed in aprotic and apolar solvents. The possibility of solvent-dependent tuning of substrate selectivity/affinity and the high binding capacity recommend the developed MIPs as promising solid-phase extraction adsorbents for clean-up and pre-concentration of OTA from various biologically relevant matrices.     

酚酞分子印迹聚合物的制备及特异吸附性能

以泻药酚酞为模板分子,4-乙烯基吡啶为功能单体制备了模板分子和功能单体不同比例的一系列酚酞分子印迹聚合物。利用扫描电镜对聚合物进行了表面形态分析,采用静态平衡实验法研究了聚合物对模板分子及其类似物的吸附行为和选择性识别能力。实验结果表明,所制备的分子印迹聚合物,吸附 3 h 后基本接近最大吸附量,其中模板分子、4-乙烯基吡啶和交联剂的摩尔比为 1∶6∶20的MIP2的印迹因子为 2.30,效果最佳。Scatchard 分析表明, 在所研究的浓度范围内,吸附过程存在两类结合位点,一类高亲和力结合位点的离解常数为Kd1= 0.63 mmol/L,最大表观结合量 Qmax1 = 25.4 umol/g,另一类低亲和力结合位点的离解常数为 Kd2 =3.5 mmol/L,最大表观结合量 Qmax2 = 61.9 umol/g,通过与酚酞类似物质在酚酞分子印迹聚合物上的吸附行为比较,表明对酚酞具有很好的选择性吸附。     

Molecularly imprinted solid-phase extraction of matrine from radix Sophorae tonkinensis

In the study, molecularly imprinted polymers (MIPs) with special molecular recognition properties of matrine (MAT) were prepared in our lab, using melamine-urea-formaldehyde (MUF) as the functional monomer and matrine as the template. An equilibrium binding experiment was performed to investigate the binding ability of the MIPs, and indicated that the MIPs had a high adsorption and good elution ability to the target molecule MAT, when the template/functional monomer ratio (T/M) was 5 mg g(-1). Scatchard analysis and isothermal equilibrium adsorption indicated that only one kind of binding site had existed in the MAT-imprinted polymers with its dissociation constants estimated to be 3.31 × 10(-4) mol L(-1) (200-400 mesh (inch(-1))) and 6.83 × 10(-4) mol L(-1) (over 400 mesh (inch(-1))) depending on the mesh of the MIPs. MAT purification and elution experiments were carried out using MIPs as the solid-phase extraction (MISPE) sorbent, and acetone, water, and chloroform as the elution solvents. The results demonstrated that MIPs achieved their highest adsorption capability after treatment with alkaline solution, while acetone was the most efficient elution solvent. Then, a crude extraction of matrine in radix Sophorae tonkinensis was performed using these MIPs as the separation medium. The results showed that MIPs had a high MAT selectivity, and the amount of matrine content obtained by MISPE was 1.4-fold to that obtained by liquid-liquid extraction.     

Evaluation of new selective molecularly imprinted polymers prepared by precipitation polymerisation for the extraction of phenylurea herbicides

Three different molecularly imprinted polymers (MIPs) have been prepared by precipitation polymerisation using linuron (LIN) or isoproturon (IPN) (phenylurea herbicides) as templates and methacrylic acid (MAA) or trifluormethacrylic acid (TFMAA) as functional monomers. The ability of the different polymers to selectively rebind not only the template but also other phenylurea herbicides has been evaluated. In parallel, the influence of the different templates and functional monomers used during polymers synthesis on the performance of the obtained MIPs was also studied through different rebinding experiments. The experimental binding isotherms were fitted to the Langmuir-Freundlich isotherm allowing to describe the kind of binding sites present in the imprinted polymers under study. It was concluded that TFMAA-based polymer using IPN as template presents the best properties to be used as a selective sorbent for the extraction of phenylurea herbicides.     

Variable selection in near-infrared spectroscopy: benchmarking of feature selection methods on biodiesel data

In the present work, microwave heating initiated precipitation polymerization was developed to prepare podophyllotoxin (PPT) molecularly imprinted polymers (MIPs), resulting in much shorter polymerization time and better particle morphology. Prior to the polymerization, ultraviolet and FTIR spectroscopy were used to study the interactions between PPT and the functional monomers. The synthesized parameters were respectively optimized and the optimal conditions for the efficient adsorption property were template: PPT, 1 mmol; functional monomer: acrylamide, 6 mmol; bi-crosslinker: ethylene glycol dimethacrylate, 20 mmol and divinylbenzene, 20 mmol; porogen: acetonitrile, 40 mL; initiator: azobisisobutyronitrile, 0.01mol L?1; polymerization temperature: 60°C. FTIR spectroscopy, SEM and thermal analysis were used to characterize the MIPs. The results of the equilibrium rebinding experiments and the competitive adsorption experiments showed that these imprinted polymers exhibited good adsorption ability for the PPT. Scatchard analysis illustrated that two and one types of binding sites were generated in the MIPs and non-imprinted polymers (NIPs), respectively. Using the prepared MIPs as the solid phase extraction (SPE) sorbent, PPT was extracted selectively and efficiently from Dysosma versipellis, Sinopodophyllum hexandrum and Diphylleia sinensis. The regression equation was y=5.873×10?x+17075.659 with the correlation coefficient of 0.9994 in the concentration range of 0.005-0.4 mg mL?1. After washing and eluting the SPE column with methanol and MeOH/acetic acid solution (v/v, 9:1), the limits of detection were 0.12-0.18 μg mL?1 and their recoveries were in the range of 89.5-91.1% with all RSDs lower than 3.7.