烯酰吗啉分子印迹聚合物的合成及固相萃取研究

以烯酰吗啉为名义模板,甲基丙烯酸(MAA)为功能单体,二甲基丙烯酸乙二醇酯(EDMA)为交联剂,在制孔剂三氯甲烷中制备了烯酰吗啉的分子印迹聚合物。优化的模板、MAA及EDMA间的配比为1∶4∶20。采用本体聚合和悬浮聚合两种聚合方法进行MIP的制备,探讨两种聚合方法的不同及优缺点。研究还以分子印迹聚合物作为固相萃取的填料,制备固相萃取柱,对其应用性能进行评价。     

Investigation of Oleuropein Content in Olive Leaf Extract Obtained by Supercritical Fluid Extraction and Soxhlet Methods

The separation processes of the phenolic compounds from solid plant matrixes are of great importance. In the scope of developing more efficient methods to separate olive leaf extract, dried and ground olive tree leaves from Aegean region of Turkey were extracted by means of Soxhlet and supercritical fluid extraction (SFE) methods. In the Soxhlet method, different types of solvents (hexane, water, ethanol, methanol, and methanol/hexane (3:2, v/v) mixture) were used to determine the effect of the solvent type on the extraction performance. In the SFE method, the effect of pressure (100–300 bar), temperature (50 and 100°C), and type of co-solvent on the amount of both extract and oleuropein were investigated. Ethanol, methanol and water were selected as co-solvent in 20% (v/v) amount. Quantitative analysis was performed by using a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) technique. The results of SFE were compared with those obtained by the Soxhlet method. Whereas the highest oleuropein yield was achieved via the Soxhlet method through methanol with the value of 37.84 mg/g dried leaf, the best oleuropein yield was achieved with the value of 14.26 mg/g dried leaf by using CO₂ modified by methanol at 300 bar and 100°C in the SFE method.     

Molecularly Imprinted Polymer for Solid-Phase Extraction of Phenolic Acids from Salicornia herbacea L.

This paper reports the application of a molecularly imprinted polymer (MIP) for the extraction and separation of phenolic acids from Salicornia herbacea L. (S. herbacea) using a solid phase extraction (SPE) system. The template of the MIP for phenolic acid extraction and separation was selected experimentally as one of seven templates. The obtained material with Benzoic acid (BA) as a template had the best extraction capacity of phenolic acids from S. herbacea. Water and methanol/HCl were selected as a washing solvent and elution solvent, respectively. The good linearity was obtained for the three targets, ranging from 10 to 500 μg mL^?1 (R² > 0.999), with relative standard deviations ≤ 5.0%. Overall, the proposed method using MIPs is expected to have a wide range of applications.     

分子印迹杂化材料的溶胶-凝胶法制备及选择性固相萃取牛奶中洛美沙星

以兽药洛美沙星为模板分子,3-氨基丙基三乙氧基硅烷为功能单体,甲基三甲氧基硅烷为交联剂,采用溶胶-凝胶分子印迹技术,以离子对及疏水作用方式,在水相体系中合成了具有分子识别作用的的新型有机-无机杂化分子印迹聚合物。静态吸附和Scatchard分析实验结果表明,此印迹材料对洛美沙星的结合存在两个结合位点,最大吸附容量分别为95.65与127.45μmol/g。以此印迹材料作为固相萃取剂,优化萃取条件,成功应用于牛奶中洛美沙星测定。     

分子印迹固相萃取技术在食品安全检测中的应用进展

分子印迹固相萃取技术(MISPE)是一种高效的样品前处理技术,能从复杂的样品中选择性分离目标物及其结构类似物。分子印迹技术(MIT)在食品中农药和兽药残留检测中的应用得到快速发展。综述了近两年国内外分子印迹固相萃取技术在食品安全检测中农药、兽药残留检测的应用及进展,讨论了当前分子印迹固相萃取技术在食品安全检测应用中存在的问题,并对其发展趋势进行了展望。     

油橄榄中橄榄苦苷的提取及纯化工艺研究

采用ODS C18色谱柱,流动相为甲醇:水(0.2%醋酸)体积比45:55,检测波长为230 nm,建立油橄榄叶中橄榄苦苷的HPLC分析方法。采用单因素和正交试验筛选优化油橄榄叶橄榄苦苷浸提的最佳工艺,并进一步研究大孔树脂静态和动态吸附和解吸附性能。结果表明:1)热回流浸提的最佳工艺为乙醇体积分数80%,温度70℃,提取时间3.5 h,料液比1:15(g:mL),提取次数2次。2)通过对比不同树脂对橄榄苦苷的吸附,筛选出选择性吸附好的AB-8树脂,吸附量为每克湿树脂32.1 mg。AB-8树脂纯化的最佳条件为:上样质量浓度为2 g/L,70%乙醇-水洗脱,流速为3 mL/min,洗脱液用量为3 BV。3)橄榄苦苷的粗提物经过AB-8树脂纯化后,橄榄苦苷的纯度达到47.90%,黄酮含量为16.4%,收率为6.43%。     

分子印迹材料的制备与应用

分子印迹技术(molecularly imprinted technique,MIT)来源于免疫学、生物化学,是模拟生物体内抗体与抗原、酶与底物等分子之间的识别过程,是合成对某一种分子具有专一识别性的聚合物的方法。本文对分子印迹材料的合成方法——共价法、非共价法和半共价法等进行了综述,并介绍了分子印迹材料与技术在分析化学与生物领域的应用。     

分子印迹聚合物在分离技术中的研究进展

由于分子印迹聚合物 (MIP)所具有的独特的预定选择性 ,它在分离技术中的应用研究已受到了普遍关注 ,本文将从MIP的基本概念、制备方法及其在分离技术中的应用等方面对MIP在分离技术中的研究进行简单的评述。引用文献 40篇     

Synthesis and Characterization of Molecularly Imprinted Polymers for Phenoxyacetic Acids

2-methylphenoxyacetic acid (2-MPA), 2-methyl-4-chlorophenxyacetic acid (MCPA) and 4-chlorophenoxyacetic acid (4-CPA) were imprinted to investigate the cross-selectivities of molecularly imprinted polymers (MIPs). The result indicates that 2-MPA, which is similar in shape, size and functionality with phenoxyacetic herbicides, are suitable to be used as a suitable template to prepare the MIPs for retaining phenoxyacetic herbicides. To study the ion-pair interactions between template molecules and functional monomer 4-vinylpiridine (4-VP), computational molecular modeling was employed. The data indicate that the cross-selectivities of MIPs for phenoxyacetic acid herbicides depend on the binding energies of complexes.     

奎宁印迹聚合物的吸附与识别特性的研究

以奎宁为模板分子 ,利用分子印迹技术合成了一种新型的类似于人工受体的印迹聚合物 ,研究了它对奎宁和其它底物的吸附特性和选择性识别能力 ,并对其固相萃取性能做了初步的研究。     

Studies on the Detection of Oleuropein from Extra Virgin Olive Oils Using Enzymatic Biosensors

Oleuropein (OLEU) is an important indicator of the quality and authenticity of extra virgin olive oils (EVOO). Electrochemical sensors and biosensors for the detection of oleuropein can be used to test the adulteration of extra virgin olive oils. The present study aimed at the qualitative and quantitative determination of oleuropein in commercial EVOO samples by applying electrochemical techniques, cyclic voltammetry (CV) and square wave voltammetry (SWV). The sensing devices used were two newly constructed enzyme biosensors, supported on single-layer carbon-nanotube-modified carbon screen-printed electrode (SPE/SWCNT) on whose surface tyrosinase (SPE/SWCNT/Tyr) and laccase (SPE/SWCNT/Lac) were immobilized, respectively. The active surfaces of the two biosensors were analyzed and characterized by different methods, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FTIR) and the results confirmed the efficient immobilization of the enzymes. SPE/SWCNT/Tyr was characterized by a low detection limit (LOD = 9.53 × 10⁻⁸ M) and a very good sensitivity (0.0718 μA·μM⁻¹·cm⁻²) over a wide linearity range from 0.49 to 11.22 μM. The process occurring at the biosensor surface corresponds to kinetics (h = 0.90), and tyrosinase showed a high affinity towards OLEU. The tyrosinase-based biosensor was shown to have superior sensitive properties to the laccase-based one. Quantitative determination of OLEU in EVOOs was performed using SPE/SWCNT/Tyr and the results confirmed the presence of the compound in close amounts in the EVOOs analysed, proving that they have very good sensory properties.     

Nanopore Molecularly Imprinted Polymer Membranes for Environmental Usage: Selective Separation of 2,4-Dichlorophenoxyacetic Acid as a Toxic Herbicide from Water

Nanopore molecularly imprinted polymers and membranes for selective separation of 2,4-dichlorophennoxyacetic acid were prepared using 2,4-dichlorophennoxyacetic acid as a template molecule, methacrylic acid as a functional monomer and trimethylolpropane trimethacrylate as a cross linker. Recognition properties of molecularly imprinted membranes were evaluated by performing binding experiments with analog phenoxyacetic acid. Flux, permeability, and permselectivity of the membranes as well as their properties were studied. Molecularly imprinted membrane-2 showed the equilibrium binding capacity of 34.57 mg/g and a selectivity factor of 12.96 toward 2,4-dichlorophennoxyacetic acid at 500 mg/l concentration. Permeability experiments indicated that molecularly imprinted membrane can recognize and absorb 2,4-dichlorophennoxyacetic acid from aqueous solutions’ selectively.     

Comparison of molecular adsorption ability of the molecularly imprinted polymers prepared by ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate as cross linkers

The target of this study was to synthesize the molecularly imprinted polymers (MIPs) of L ‐phenylalanine as the solid phases for characterization of molecular adsorption by molecularly imprinted solid phase extraction (MISPE). These MIPs, in microscale, were synthesized using thermal (40°C)‐compared with thermal (65°C)‐initiated polymerization process. Itaconic acid was chosen as the functional monomers, and either ethylene glycol dimethacrylate or trimethylolpropane trimethacrylate (TRIM) was used as the cross linker and was compared together. The influences of several parameters on the properties of the MIPs were investigated, especially physical robustness from the percentage yields and molecular adsorption from the percentage recovery by MISPE. The best yields were obtained from polymers made using TRIM and thermal (65°C)‐initiated polymerization. However, there were no significant differences in molecular adsorption. It was concluded that these parameters can be considered to synthesize MIPs for chiral separation in advance steps such as other related chromatographic techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2325–2330, 2007     

分子印迹固相萃取法提取花生壳中木犀草素

采用分子印迹技术,以木犀草素为模板分子、丙烯酰胺为功能单体、EGDMA为交联剂,合成了木犀草素印迹聚合物。将该印迹聚合物用于固相萃取,分离提取花生壳中的木犀草素。结果表明,该印迹聚合物对木犀草素具有较高的吸附性能和选择性,用印迹柱萃取得到的木犀草素纯度高出硅胶柱分离近20个百分点,达到96.2%。且MIPs-SPE柱与普通的硅胶柱相比,经过洗脱再生后可以反复使用多次。     

分子印迹技术在固相萃取中的应用

分子印迹技术是制备具有分子特异识别功能聚合物的一种技术。分子印迹固相萃取技术由于具有高通量和高特异性,在食品、环境、药物、生物样品中分析物的分离、净化、富集中具有广阔的应用前景。文章中综述了分子印迹固相萃取技术的应用、分子印迹技术的最新进展和在应用中存在的问题等。     

Application of Molecularly Imprinted Polymer for Extraction and Determination of Nalidixic Acid by High-Performance Liquid Chromatography

Nalidixic acid imprinted polymer has high application potential in clinical purposes. Molecularly imprinted polymers were prepared using nalidixic acid as the template molecule. The polymer was synthesized in a non-covalent approach with N,N-dimethylacrilamid and allyl glycidyl ether/iminodiacetic acid as the functional monomer. The effects of various parameters such as pH and adsorption time on adsorption capacity were considered. It was confirmed that the binding ability of the prepared molecularly imprinted polymer for nalidixic acid was essentially sufficient in the presence of the other compounds coexisting in human urine.     

Synthesis and Evaluation of a Molecularly Imprinted Polymer for Solid Phase Extraction of Ethopabate from Chicken Tissue

In this paper the development and evaluation of a molecularly imprinted polymer (MIP) for ethopabate is described. Ethopabate (ETP), 4-acetamido-2-ethoxybenzoic acid methyl ester, is one of the antibiotics which is used as coccidiostat in poultry feeds. In the present study, two widely used functional monomers, methacrylic acid (MAA) and 4-vinylpyridine (4-VP) were compared theoretically and experimentally as the candidates for MIP preparation. Hyperchem software was employed to estimate binding energies between ETP and functional monomers and batch rebinding experiments were performed to study the binding characteristics of the polymers. The results showed that MAA is a better functional monomer to prepare MIP. UV/Vis and NMR spectroscopy were used as two common tools to study the interactions between ETP and MAA in the pre-polymerization mixture. Liquid chromatography experiments showed that the prepared MIP has recognition capability toward ETP in comparison with other structurally related compounds. The ETP-imprinted polymer was further applied for selective solid phase extraction (SPE) of ETP from a chicken tissue sample. The extraction yield of ETP was found to be quantitative (87 ± 3%) and the LOD and LOQ based on 3 and 10 times of the noise of HPLC profile were 0.05 and 0.32 ng ml^?1, respectively. It was confirmed that the binding ability of the prepared MIP for ETP was essentially sufficient in the presence of other compounds coexisting in tissue sample. Therefore, as a selective and efficient solid phase material, ETP-imprinted polymer has a high potential application in the analysis of residues of this antibiotic in chicken tissue samples.     

Molecularly Imprinted Composite Membranes for Selective Detection of 2-Deoxyadenosine in Urine Samples

An important challenge for scientific research is the production of artificial systems able to mimic the recognition mechanisms occurring at the molecular level in living systems. A valid contribution in this direction resulted from the development of molecular imprinting. In this work, a novel molecularly imprinted polymer composite membrane (MIM) was synthesized and employed for the selective detection in urine samples of 2-deoxyadenosine (2-dA), an important tumoral marker. By thermal polymerization, the 2-dA-MIM was cross-linked on the surface of a polyvinylidene-difluoride (PVDF) membrane. By characterization techniques, the linking of the imprinted polymer on the surface of the membrane was found. Batch-wise guest binding experiments confirmed the absorption capacity of the synthesized membrane towards the template molecule. Subsequently, a time-course of 2-dA retention on membrane was performed and the best minimum time (30 min) to bind the molecule was established. HPLC analysis was also performed to carry out a rapid detection of target molecule in urine sample with a recovery capacity of 85%. The experiments indicated that the MIM was highly selective and can be used for revealing the presence of 2-dA in urine samples.     

吲哚-3-乙酸分子印迹聚合物的合成及吸附性能分析

以吲哚-3-乙酸(indole-3-acetic acid,IAA)为模板、甲基丙烯酸为功能单体、乙腈为致孔剂,采用本体聚合法合成了对IAA有特异性识别的吲哚-3-乙酸分子印迹聚合物(IAA-MIP)。红外光谱分析表明,IAA是以氢键形式结合在聚合物的空腔中。等温吸附线及Scatchard分析表明,洗脱模板后的IAA-MIP结合IAA的能力比空白印迹聚合物(NIP)强,且有2种结合方式,其解离常数分别为KD1=1.04×10-6 mol·L-1和KD2=9.23×10-6 mol·L-1,最大表观结合位点分别为Bmax1=0.10μmol·g-1和Bmax2=0.28μmol·g-1。对植物样品的固相萃取实验表明,洗脱模板后的IAA-MIP对IAA具有较强的特异性吸附能力。     

分子印迹技术手性分离氨基酸衍生物(Ⅰ)—分子印迹聚合物的制备、色谱评价及物理化学表征

利用分子印迹技术制备了对L 特丁氧羰基色氨酸或D 特丁氧羰基色氨酸印迹的丙烯酰胺分子印迹聚合物。色谱评价结果表明,印迹分子L Boc Trp的离解常数(3 287mmol/L)要小于非印迹分子D Boc Trp的离解常数(4 379mmol/L),说明分子印迹聚合物对印迹分子具有特异亲和作用。采用扫描电镜和红外光谱等物理化学表征技术从结构上对这种特异性作了进一步的分析。结果表明,分子印迹聚合物是一种具有多层次孔结构的聚合物,为溶质的扩散提供了良好的通道;在聚合物表面存在可与印迹分子相互作用的官能团。