L-肉碱分子表面印迹聚合物的制备及其识别性能研究

以L-肉碱(L-carnitine)作为印迹模板分子,甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,采用硅胶表面分子印迹技术合成了L-肉碱分子印迹聚合物(MIP)和非印迹聚合物(NMIP).通过紫外光谱研究了MAA与L-肉碱之间的结合作用.利用IR和SEM测试分别对产物进行了结构表征和表面形貌观察,说明分子印迹聚合物成功接枝到了硅胶表面.吸附动力学实验结果表明,MIP对L-肉碱有较好的识别性和吸附性;Scatchard分析表明该印迹聚合物中存在着一类等价的结合位点,最大表观结合量为71.00μmol/g,离解常数Kd=2.76×10-4mol/L;选择性吸附实验结果表明,MIP对L-肉碱的吸附结合量高于其D型异构体和其他类似物;拆分实验结果表明,MIP对DL-肉碱的拆分有一定作用.     

硅胶表面水胺硫磷分子印迹聚合物的制备及其性能

以水胺硫磷为模板分子,甲基丙烯酸(MAA)为功能单体,三羟甲基丙烷三甲基丙烯酸酯(TRIM)为交联剂,采用表面分子印迹技术,以商品化硅胶为基体,合成了对有机磷农药水胺硫磷具有良好选择性的表面分子印迹聚合物(MIP)。用红外光谱(IR)、扫描电子显微镜(SEM)和元素分析等技术分别对表面印迹聚合物进行了结构表征和表面形态观察;静态吸附平衡实验和Scatchard分析表明,该印迹聚合物中存在着两类不同的结合位点,离解常数分别为4.84×10-3和15.2×10-3mol/L。与非印迹聚合物相比,MIP对水胺硫磷有较大的特异性吸附能力,其印迹因子为2.73。     

用于分子识别的分子印迹聚合物固定相

着重介绍了分子印迹聚合物（MIP）作为一种分离介质在手性化合物拆分方面的应用,系统总结了分子印迹的原理和MIP的4种合成方法,初步探讨了MIP的分子识别机理,并阐述了它的应用以及优点和缺点。     

非诺贝特印迹聚合物的制备与性能研究

以非诺贝特(FNB)为模板分子,α-甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,采用本体聚合方法合成了FNB分子印迹聚合物(MIP)。IR和SEM表征的结果显示:FNB分子印迹聚合物中存在与模板分子相互作用的特征基团,与空白聚合物(NIP)的表面形态显著不同,说明MIP存在与模板分子相互识别的结合位点。采用静态平衡结合方法和Scatchard模型评价了FNB分子印迹聚合物的结合特性和识别机理,并考察了其选择性吸附能力。结果表明,FNB分子印迹聚合物存在能量相异的两类特异性结合位点,对FNB具有高选择吸附特性,饱和吸附量为6.363mg/g。     

硅胶表面水胺硫磷分子印迹聚合物的制备及其性能

以水胺硫磷为模板分子,甲基丙烯酸（MAA）为功能单体,三羟甲基丙烷三甲基丙烯酸酯（TRIM）为交联剂,采用表面分子印迹技术,以商品化硅胶为基体,合成了对有机磷农药水胺硫磷具有良好选择性的表面分子印迹聚合物（MIP）。 用红外光谱（IR）、扫描电子显微镜（SEM）和元素分析等技术分别对表面印迹聚合物进行了结构表征和表面形态观察;静态吸附平衡实验和Scatchard分析表明,该印迹聚合物中存在着两类不同的结合位点,离解常数分别为4.84×10-3和15.2×10-3 mol/L。与非印迹聚合物相比,MIP对水胺硫磷有较大的特异性吸附能力,其印迹因子为2.73。     

光接枝表面修饰法制备牛血红蛋白的分子印迹微球

聚苯乙烯球载体表面经引发转移终止剂修饰后, 采用光接枝表面印迹方法制备了以牛血红蛋白(BHb)为模板分子、丙烯酰胺为功能单体和N,N′-亚甲基双丙烯酰胺为交联剂的分子印迹聚合物微球(MIP). 进一步采用红外光谱(IR)、扫描电子显微镜(SEM)和元素分析对聚合物微球进行了表征, 证实了载体表面成功地接枝了分子印迹层, 并研究了其吸附性能和分子识别选择性能. 结果表明, 采用光接枝表面修饰法制备的分子印迹微球对模板分子有着很好的吸附容量和识别选择性.     

声表面波分子印迹技术检测甲基膦酸二甲酯的研究

以分子印迹(MIP)电聚合的成膜方法,在声表面波(SAW)双通道延迟线上制备了对甲基膦酸二甲酯(DMMP)有选择性的分子印迹薄膜(纳米级),并证实了分子印迹的明显效果,所研制的声表面波分子印迹传感器／(SAW—MIP)对甲基膦酸二甲酯的检出限为5mg／m^3。     

磁性吡嘧磺隆印迹聚合物的制备及性能研究

以包覆Si O2的Fe3O4为载体,吡嘧磺隆(PS)为模板分子,甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,通过表面印迹法制备了磁性PS分子印迹聚合物(MIP),采用红外光谱、扫描电镜对其结构进行表征,采用吸附实验对其性能进行研究,并以MIP为固相萃取填料,结合高效液相色谱进行检测。结果表明,MIP对PS的饱和吸附量为68.94mg/g,印迹因子为2.49。将本方法应用于大米中PS残留分析,回收率在87.73%~99.57%范围内,相对标准偏差低于5.51%。所制备的MIP对样品中PS的富集、分离效果良好。     

胆酸印迹聚合物的制备及在含水介质中的结合性能

为了在含水介质中进行有效印迹,本研究中以双甲基丙烯酰-β-环糊精（BMA-β-CD）和2-(二乙基胺基)乙基甲基丙烯酸酯(DEAEM)为功能单体制备了胆酸印迹聚合物MIP1,并用平衡结合实验研究了MIP1在含水介质中对模板分子的识别能力。结果表明,MIP1比单独以BMA-β-CD或DEAEM为功能单体制备的印迹聚合物MIP2和MIP3,显示出对模板分子更好的选择性结合能力。MIP1的特异性吸附量ΔCP为38.81μmol/g,印迹因子IF为2.46。研究表明,在含水介质中,利用模板分子与功能单体之间的疏水作用和离子作用是提高印迹聚合物分子识别能力的关键。研究还表明,在识别过程中,疏水作用在驱动分子进入印迹孔穴时起重要作用。     

外消旋酪氨酸印迹聚合物的制备及性能研究

以外消旋酪氨酸(DL-Tyr)为模板分子,合成的(L-)-N-烯丙基吡咯烷基-2-羰基酯(L-APCA)作为手性功能单体,优化印迹体系和聚合方法合成了12种印迹聚合物(MIP1-12)。采用氮气吸附实验和扫描电镜表征最优聚合物MIP12的结构,并结合HPLC法分析MIP12对外消旋体DL-Tyr的手性拆分能力。研究结果表明:采用表面印迹聚合法,以纳米二氧化硅(nano-Si O2)为载体制备的印迹聚合物MIP12具有最优的印迹效果,对外消旋DL-Tyr有较好的手性拆分能力,拆分因子达到2.53。说明以L-APCA为手性功能单体直接印迹外消旋酪氨酸制备手性印迹材料是可行的,具有较好的应用前景。     

Electrochemistry of molecular imprinting of large entities

Molecularly imprinted polymer (MIP) is a well-known approach, in which cavities with specific affinity are formed. These functional materials are used mostly for the separation, sensing, and catalysis of small molecules. In the last two decades, the MIP concept has been expanded for the imprinting of large entities such as nanoparticles, viruses, and cells. In this emerging field termed surface imprinted polymers (SIPs), a thin matrix imprints only part of the entity to enable its easy removal and rebinding.In this review, we focus on the different recent imprinting strategies for nanoparticles, viruses, and cells in conjunction with electrochemistry and describe their applications in the fields of biology, analytical chemistry, and medicine.     

粉煤灰基氧氟沙星分子印迹聚合物的制备及其应用

以工业废料粉煤灰微球为基质,氧氟沙星 (OFL) 为模板分子,采用表面印迹法制备印迹材料MIP。通过紫外光谱法结合理论分析选择实验条件,并对该印迹材料结构、吸附行为进行研究。结果表明,该印迹材料对氧氟沙星具有良好的特异识别性和优良的亲和性。与以硅胶为载体制备的印迹聚合物相比,该材料吸附容量更高和印迹效果更好。将其作为固相萃取填料对鸡产品进行分离富集,与C18柱相比,分离富集效果更好。结合UPLC,对实际样品中氧氟沙星进行分析,回收率为82.0%-96.7%,相对标准偏差低于5.5%,可用于鸡产品中氧氟沙星分离分析。     

Dual‐templates molecularly imprinted monolithic columns for the evaluation of serotonin and histamine in CEC

To extend the application of molecularly imprinted polymers, the dual‐templates molecularly imprinted monolithic columns were developed in a capillary format. Two templates serotonin and histamine were simultaneously imprinted using two different functional monomers such as methacrylic acid (MAA) and methylenesuccinic acid (MSA) in a mixture of ethylene glycol dimethacrylate (EDMA) as a cross‐linker and AIBN as polymerization initiator dissolved in DMF as porogen. The resulting molecular imprinted polymers (MIPs) were characterized based on their performance in the CEC separation of two imprinted templates. The optimization parameters such as pH, ACN composition, and concentration of the eluent were varied to achieve best resolution and efficiency for CEC separation of templates with each MIP column. It was found that the MIP monolith column fabricated using MSA offered better resolution and separation efficiency compared to column fabricated with MAA. This work utilized the dual‐templates imprinting approach successfully and broadens the scope of multi‐templates imprinting capabilities in capillary format in CEC application.     

A thermosensitive monolithic column as an artificial antibody for the on-line selective separation of the protein

The main objective of this study was to develop a new methodology for the preparation of a protein (antigen) that is a molecularly imprinted polymer (MIP, an artificial antibody) modified onto the surface of a silica skeleton in which the resulting stationary phase is thermosensitive. The silica monolithic skeleton with vinyl groups was synthesized in a stainless-steel column by using a mild one-step sol-gel process with two types of precursor: methyltrimethoxysilane (MTMS) and γ-methacryloxypropyltrimethoxysilane (γ-MAPS). Subsequently, three types of the thermosensitive protein MIP were anchored onto the surface of the silica skeleton to prepare the MIP monoliths, which were systematically investigated for back pressure and separation ability at different temperatures to establish good imprinting conditions. Under the optimized imprinting conditions, the chromatographic behavior of the thermosensitive MIP monolith exhibited strong retention ability for the lysozyme template (target antigen) in relation to the nonimprinting monolith (NIP monolith). The imprinting factor (IF) for lysozyme reached 3.48 at 20 °C. Moreover, this new type of artificial antibody displayed favorable binding characteristics for lysozyme over competitive proteins and was further evaluated to selectively separate lysozyme in a real sample by using an on-line method. The run-to-run and column-to-column repeatability measurements of the thermosensitive MIP monoliths were also satisfactory.     

Preparation and recognition performance of cytisine alkaloid‐imprinted material prepared using novel surface molecular imprinting technique

Methacrylic acid was first graft‐polymerized on the surfaces of micron‐sized silica gel particles in the manner of “grafting from” using 3‐methacryloxypropyl trimethoxysilane as an intermedia, obtaining the grafted particle polymethacrylic acid PMAA/SiO₂. By adopting the novel surface‐molecular imprinting technique put forward by us, cytisine molecule‐imprinted material MIP‐PMAA/SiO₂ was prepared with ethylene glycol diglycidyl ether as crosslinking agent. The binding characteristics of MIP‐PMAA/SiO₂ towards cytisine was investigated in depth with both batch and column methods and using matrine and oxymatrine as two contrast alkaloids, which with cytisine coexist in sophora alopecuroides and their chemical structure is similar to cytisine to a certain extent. The experimental results show that the surface‐imprinted material MIP‐PMAA/SiO₂ has excellent binding affinity for cytisine (20.1 g/100 g of binding capacity), and it is more important that MIP‐PMAA/SiO₂ has very high recognition selectivity for cytisine in relation to the two contrast alkaloids. The selectivity coefficients of the grafted particles PMAA/SiO₂ (non‐imprinted material) for cytosine in relation to matrine and oxymatrine are only 1.03 and 1.06, respectively, displaying no recognition selectivity for cytisine. However, after imprinting, the selectivity coefficient of MIP‐PMAA/SiO₂ for cytisine in respect to matrine and oxymatrine are remarkably enhanced to 12.08 and 15.05, respectively.     

Molecularly Imprinted Nanogels Acquire Stealth In Situ by Cloaking Themselves with Native Dysopsonic Proteins

Protein corona formation was regulated on the surface in vivo by molecular imprinting to enable polymeric nanogels to acquire stealth upon intravenous administration. Albumin, the most abundant protein in blood, was selected as a distinct protein component of protein corona for preparing molecularly imprinted nanogels (MIP‐NGs) to form an albumin‐rich protein corona. Intravital fluorescence resonance energy transfer imaging of rhodamine‐labeled albumin and fluorescein‐conjugated MIP‐NGs showed that albumin was captured by MIP‐NGs immediately after injection, forming an albumin‐rich protein corona. MIP‐NGs circulated in the blood longer than those of non‐albumin‐imprinted nanogels, with almost no retention in liver tissue. MIP‐NGs also passively accumulated in tumor tissue. These data suggest that this strategy, based on regulation of the protein corona in vivo, may significantly influence the development of drug nanocarriers for cancer therapy.     

Mechanism of molecular recognition on molecular imprinted monolith by capillary electrochromatography

The recognition mechanism of molecularly imprinted polymer (MIP) in capillary electrochromatography (CEC) is complicated since it possesses a hybrid process, which comprises the features of chromatographic retention, electrophoretic migration and molecular imprinting. For an understanding of the molecular recognition of MIP in CEC, a monolithic MIP in a capillary with 1,1'-binaphthyl-2,2'-diamine (BNA) imprinting was prepared by in situ copolymerization of imprinted molecule, methacrylic acid and ethylene glycol dimethacrylate in porogenic solvent, a mixture of toluene-isooctane. Strong recognition ability and high column performance (theory plates was 43,000 plates/m) of BNA were achieved on this monolithic MIP in CEC mode. In addition, BNA and its structural analogue, 1,1'-bi-2, 2'-naphthol, differing in functional groups, were used as model compounds to study imprinting effect on the resultant BNA-imprinted monolithic column, a reference column without imprinting of BNA and a open capillary. The effects of organic modifier concentration, pH value of buffer, salt concentration of buffer and column temperature on the retention and recognition of two compounds were investigated. The results showed that the molecular recognition on MIP monolith in CEC mode mainly derived from imprinting cavities on BNA-imprinted polymer other than chromatographic retention and electrophoretic migration.     

分子印迹聚合物颗粒在毛细管电色谱中的应用

依据分子印迹技术(MIT)制备的分子印迹聚合物(MIP)颗粒对模板分子及其结构类似物具有特异性识别和选择性吸附作用,同时具有较大的比表面积和快速的传质动力学特性,因而被广泛用作液相色谱固定相和固相萃取材料。将MIP颗粒作为固定相应用于毛细管电色谱(CEC),结合了CEC的快速、高效和MIP的高亲和性、高选择性的特点,成为分析科学领域最具有发展前景的分离技术之一。MIP颗粒在CEC领域有几种不同的应用形式: 作为填充材料填充到毛细管柱中;作为嵌入材料嵌入到毛细管柱内部不同基质的骨架中;作为准固定相添加到CEC运行缓冲溶液中。本文综述了近几年MIP颗粒在CEC领域应用的发展,对该领域今后的发展前景进行了展望。