加替沙星印迹聚合物的制备及结合特性研究

以微米级聚苯乙烯微球为种子、加替沙星为模板分子,采用单步溶胀聚合法,在水相中制得了分子印迹聚合物微球(MIPMs)。通过紫外光谱研究MIPMs的识别机理;利用红外光谱分析MIPMs的结合位点,运用扫描电镜观察微球的形貌;并结合加替沙星的荧光性质,利用荧光光谱研究MIPMs的结合特性。Scatchard分析表明,MIPMs在识别加替沙星过程中存在两类结合位点,高亲和力结合位点的平衡离解常数KD1=0.603mmol/L,最大结合量Bmax1=28.62μmol/g;低亲和力结合位点的平衡离解常数KD2=3.110mmol/L,最大结合量Bmax2=74.27μmol/g。     

二茂铁甲酸分子印迹聚合物的制备和识别机理、结合特性

以二茂铁甲酸（FCA）为模板,选用不同的功能单体制备了一系列分子印迹聚合物,用平衡结合实验考察了它们对模板分子的结合性能。 结果表明,以甲基丙烯酸为功能单体制得的印迹聚合物P1对模板分子有很好的选择性,特异性吸附量ΔCP为23.18 μmol/g,印迹因子IF为2.33,竞争性结合实验结果表明,P1可以将模板分子从结构类似物中分离出来。 Scatchard方程研究表明,在研究的浓度范围内聚合物中形成了一类等价的结合位点,其对模板分子的平衡离解常数K=1.94 mmol/L,最大表观结合量Cpmax=92.33 μmol/g。 研究还表明,FCA的羧基是在聚合物的孔穴中产生识别位点的功能基,模板分子上的羧基与MAA的羧基形成双重氢键作用是分子识别的主要作用力。     

烯唑醇分子印迹聚合物的合成及其吸附性能研究

以烯唑醇为模板分子,MAA为功能单体,EDMA为交联剂,采用本体聚合法合成分子印迹聚合物。考察了采用不同比例的模板分子与功能单体合成的聚合物对烯唑醇的吸附量,通过静态吸附试验研究了烯唑醇分子印迹聚合物对烯唑醇吸附性能的影响,并进行Scatchard分析。由Scatchard分析可知模板分子烯唑醇与功能单体MAA形成了1类结合位点,结合位点的离解常数KD=0.117mmol/L,最大表观结合量Qmax=38.66μmol/g。     

基于金属卟啉的甲基磷酸二甲酯分子印迹聚合物微球的合成及性能

合成了分别以5-(4-甲基丙烯酰氧苯基)-10,15,20-三苯基锌卟啉(ZnMOTPP)和5-(4-甲基丙烯酰氧苯基)-10,15,20-三苯基钆卟啉(GdMOTPP)为功能单体, 甲基丙烯酸(MAA)为辅助功能单体的甲基磷酸二甲酯(DMMP)分子印迹聚合物微球. 扫描电子显微镜(SEM)表征结果表明, 微球平均粒径为50～100 μm, 粒度均匀. 与甲基丙烯酸作为功能单体的分子印迹聚合物微球的吸附性能和特异性进行对比发现, ZnMOTPP分子印迹微球的吸附性能优于 GdMOTPP分子印迹微球, 金属卟啉分子印迹微球的吸附性能优于仅以甲基丙烯酸作为功能单体的分子印迹微球, 并且微球对其印迹分子DMMP具有特异性吸附. Scatchard分析表明, DMMP分子印迹空穴中只存在一类结合位点, MIPMs-Zn+MAA的最大吸附量Q_max=148 μmol/g, MIPMs-Gd+MAA的Q_max=78.9 μmol/g, MIPMs-MAA的Q_max=13.57 μmol/g.     

沉淀聚合法制备三聚氰胺分子印迹聚合物微球

以三聚氰胺为模板分子,以甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,在乙腈-乙二醇(20∶1,V/V)混合溶剂中沉淀聚合制备了分子印迹聚合物微球.利用1H-NMR和紫外光谱方法研究了模板与功能单体相互作用情况.结果表明,三聚氰胺与甲基丙烯酸(MAA)分子通过协同氢键作用形成1∶2型氢键配合物.利用扫描电镜和红外光谱对聚合物微球的结构进行了表征.结果表明,印迹聚合物近似圆球形,粒径约为400～500 nm,且大于非印迹聚合物微球,表面存在大量的结合位点.通过静态平衡吸附实验研究了聚合物微球对模板分子的结合能力,印迹聚合物微球在4 h后逐渐达到吸附平衡,Scatchard分析表明,印迹聚合物微球主要存在两类不同的结合位点,最大表观结合量(Qmax)和平衡离解常数(Kd)分别为Qmax1=22.97μmol/g,Kd1=0.14×10-3 mol/L;Qmax2=157.65μmol/g,Kd2=2.55×10-3 mol/L,计算得出表观印迹效率和有效印迹效率分别为68%和58%.此方法合成的印迹聚合物微球对三聚氰胺有较好的结合性能,可应用于三聚氰胺的分离检测.     

辛硫磷分子印迹聚合物修饰电极的制备及应用研究

以辛硫磷为模板分子,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,偶氮二异丁腈(AIBN)为引发剂,在乙腈中沉淀聚合,研究制备了辛硫磷分子印迹聚合物(MIPs),并采用红外光谱、扫描电镜对合成的聚合物进行表征。Scatchard分析表明MIPs对辛硫磷有两种结合方式,最大表观吸附量(Qmax)和平衡解离常数(KD)分别为:Qmax1=70.58μmol/g,KD1=0.72 mmol/L;Qmax2=531.8μmol/g,KD2=7.80 mmol/L。将聚氯乙烯(PVC)5 mg和15 mg印迹聚合物超声分散于20 mL四氢呋喃(THF)中,取32μL分散液涂敷在玻碳电极上制备成辛硫磷分子印迹聚合物修饰电极,线性伏安法(LSV)检测。选择开路富集时间为5min,于0.03 mol/L HCl-0.02 mol/L KCl溶液(pH 2.2)中,辛硫磷在1.2×10-7~6.0×10-3mol/L浓度范围内,其在修饰电极上的还原峰电流与浓度的负对数呈良好的线性关系,检出限为6.0×10-8mol/L。用分子印迹聚合物修饰电极对实际样品进行分析,回收率为93.8%~96.2%。将印迹聚合物修饰电极对辛硫磷及其类似物(如三唑磷、毒死蜱、乐果等)进行检测,该电极对辛硫磷显示了良好的选择性和灵敏度。     

二茂铁甲酸分子印迹聚合物的制备、识别机理和结合特性

以二茂铁甲酸(FCA)为模板,选用不同的功能单体制备了一系列分子印迹聚合物,用平衡结合实验考察了它们对模板分子的结合性能。结果表明,以甲基丙烯酸为功能单体制得的印迹聚合物P1对模板分子有很好的选择性,特异性吸附量ΔCP为23.18μmol/g,印迹因子IF为2.33,竞争性结合实验结果表明,P1可以将模板分子从结构类似物中分离出来。Scatchard方程研究表明,在研究的浓度范围内聚合物中形成了一类等价的结合位点,其对模板分子的平衡离解常数K=1.94 mmol/L,最大表观结合量Cpmax=92.33μmol/g。研究还表明,FCA的羧基是在聚合物的孔穴中产生识别位点的功能基,模板分子上的羧基与MAA的羧基形成双重氢键作用是分子识别的主要作用力。     

紫外光聚合法制备L-DBTA手性分子印迹聚合物的研究Ⅱ.聚合物性能

以丙烯酸为功能单体,二苯甲酰-L-酒石酸(L-DBTA)为模板分子,三羟甲基丙烷三丙烯酸酯(TMPTA)为交联剂,采用紫外光聚合方法合成了L-DBTA手性分子印迹聚合物.通过HPLC表征,表明合成的手性分子印迹聚合物对L-DBTA模板分子具有很好的识别性,L-DBTA的选择性比二苯甲酰-D-酒石酸(D-DBTA)高.通过Scatchard分析表明,L-DBTA手性分子印迹聚合物中只存在一类影响聚合物识别能力的结合位点.293.15K时,结合位点的平衡离解常数为0.064mmol/L,最大表现结合容量为6.4mg/g.MIPs结合热力学研究表明,印迹分子L-DBTA与分子印迹聚合物手性识别基团之间的识别机理可以用Langmuir等温吸附描述,结合热力学参数为△H=7.40 kJ/mol,△S=42.74 J/(mol·K),△G298=-5.34kJ/mol.L-DBTA与MIPs相互作用速率快,表观活化能为7.40 kJ/mol.     

双酚A分子印迹材料的制备及其识别特性研究

以双酚A为模板分子,α-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制备了双酚A印迹聚合物。采用动态和静态两种方法研究了该印迹材料对双酚A的结合性能与分子识别特性。印迹材料对模板分子双酚A具有良好的特异性识别作用,经过Scatchard模型分析,双酚A印迹聚合物上有两类不同性质的结合位点,两种结合位点的解离常数分别为1.36和44.78 m L/g,对双酚A的最大表观吸附量分别为24.56μmol/g和312.6μmol/g。将该聚合物应用于固相萃取中,以食品包装材料为样品的加标回收实验表明,此印迹材料可以对痕量双酚A进行富集分离测定,且可重复使用。     

核-壳型苏丹红Ⅰ印迹聚合物微球制备及应用研究

以苏丹红Ⅰ为模板分子,苯基-三甲氧基硅烷(PTMOS)为功能单体,乙二醇二甲基丙烯酸酯(EGD-MA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,采用表面分子印迹技术,在自制的SiO2微球表面成功合成了对苏丹红Ⅰ具有良好选择识别性能的核-壳型印迹聚合物。采用红外光谱和扫描电子显微镜对分子印迹微球进行表征,结果表明该印迹聚合材料壳层厚度约为150 nm;采用静态吸附实验研究印迹材料对模板聚合物的吸附性能和选择特性,结果表明以PTMOS为功能单体的印迹聚合物对苏丹红Ⅰ具有优异的选择吸附性,其分离选择因子为2.62。在吸附过程中,模板分子苏丹红Ⅰ与印迹聚合物形成2种结合位点,2种结合位点的解离常数分别为2.30、10.78 mmol/L,最大表观结合量分别为27.40、128.53μmol/g。将该印迹聚合物作为固相萃取材料,对样品进行固相萃取,结合液相色谱技术成功用于辣椒油中苏丹红Ⅰ的测定。     

农药久效磷分子印迹聚合物合成及其亲合性评估

有机磷农药药效高、易于被水、酶和微生物所降解，残留毒性小，但由于不合理利用等因素，粮食、蔬菜、水果和环境中的有机磷农药残留严重超标，其危害引起了各国政府、学术界、民众的高度重视．目前有色谱法、酶法和免疫法等，这些方法的应用都受到客观因素的限制．因此研制类似于酶和抗体的高选择性、低造价、稳定性好的吸附材料用于食品和环境中有机磷农药残留的富集、分离纯化和分析尤为重要．     

Synthesis of homoveratric acid-imprinted polymers and their evaluation as selective separation materials

A bulk polymerization method was used to easily and efficiently prepare homoveratric acid (3,4-dimethoxyphenylacetic acid)-imprinted polymers from eight basic monomers: 2-vinylpyridine, 4-vinylpyridine, 1-vinylimidazole, N-allylaniline, N-allylpiperazine, allylurea, allylthiourea, and allylamine, in the presence of homoveratric acid as a template in N,N-dimethylformamide as a porogen. The imprinted polymer prepared from allylamine had the highest affinity to the template, showing an imprinting factor of 3.43, and allylamine polymers MIP8/NIP8 were selected for further studies. Their binding properties were analyzed using the Scatchard method. The results showed that the imprinted polymers have two classes of heterogeneous binding sites characterized by two pairs of K(d), B(max) values: K(d)(1) = 0.060 μmol/mL, B(max)(1) = 0.093 μmol/mg for the higher affinity binding sites, and K(d)(2) = 0.455 μmol/mL, B(max)(2) = 0.248 μmol/mg for the lower affinity binding sites. Non-imprinted polymer has only one class of binding site, with K(d) = 0.417 μmol/mL and B(max) = 0.184 μmol/mg. A computational analysis of the energies of the prepolymerization complexes was in agreement with the experimental results. It showed that the selective binding interactions arose from cooperative three point interactions between the carboxylic acid and the two methoxy groups in the template and amino groups in the polymer cavities. Those results were confirmed by the recognition studies performed with the set of structurally related compounds. Allylamine polymer MIP8 had no affinity towards biogenic amines. The obtained imprinted polymer could be used for selective separation of homoveratric acid.     

4-氨基吡啶分子模板聚合物选择性识别及结合性质的研究

以4-氨基吡啶为模板分子制备了对4-氨基吡啶具有特异选择性的模板聚合物.制得的棒状聚合物经研磨、过筛后,采用平衡结合方法评价了该模板聚合物的结合特性.Scatchard分析表明,在所研究的浓度范围内,聚合物中形成了两类不同的结合位点,这两类结合位点的离解常数采用多点结合模型计算得到的值分别为6.0μmol/L和1.2mmol/L.底物选择性表明,与其它结构相似的分子相比,该聚合物对模板分子4-氨基吡啶显示了很强的结合能力.₁HNMR研究及4-氨基吡啶共振结构分析表明,模板分子与聚合物中的结合位点之间的作用为离子作用.     

Preparation and Adsorption Characteristics of Cordycepin Molecularly Imprinted Polymers

The separation of a molecularly imprinted polymer for cordycepin was investigated. The synthesis employed cordycepin as the molecular template, alpha-methylacrylic acid as the functional monomer, glycol dimethyl acrylate as the cross-linking agent, azobisisobutyronitrile as the initiator, and tetrahydrofuran as the solvent and pore-foaming agent. The interaction between cordycepin and the functional monomer was investigated by ultraviolet-visible and infrared spectroscopy. The properties of the molecularly imprinted polymer were analyzed by scanning electron microscopy, equilibrium adsorption experiments, and the Scatchard equation. Static adsorption, solid phase extraction, and high-performance liquid chromatography experiments were employed to evaluate the adsorption properties and selective recognition characteristics. The results showed that the molecularly imprinted polymer had specific adsorption with cordycepin, and the maximum absorption capacity was 1920 µg/g. Scatchard analysis suggested that high affinity and low affinity binding sites were present. For the high affinity case, the dissociation constant and apparent maximum numbers of the binding sites were 0.0089 mmol/L and 4.78 µmol/g, respectively. The dissociation constant and apparent numbers of binding sites were 0.035 mmol/L and 6.047 µmol/g for the low affinity sites. Compared with the corresponding nonimprinted polymer, the cordycepin molecularly imprinted polymer exhibited higher adsorption and selectivity for cordycepin than structural analogs.     

盐酸强力霉素分子印迹聚合物的制备及分子识别性能

以盐酸强力霉素(DC)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、四氢呋喃(THF)为溶剂.采用本体聚合法制备了DC的分子印迹聚合物.在水溶液中,采用平衡结合方法和Scatchard模型评价了该聚合物的结合特性及识别机理,并考察了DC分子印迹聚合物的选择性吸附能力.结果表明,在所研究的浓度范围内,D...     

Design of an imprinted clean-up method for mycophenolic acid in maize

In the present work, the development of imprinted polymers selective towards mycophenolic acid and their application in food analysis are reported for the first time. To synthesize the molecularly imprinted polymer (MIP) 4-vinylpyridine and ethyleneglycol dimethacrylate were applied as functional monomer and cross-linker, respectively. Besides the toxin itself, the implementation of structural analogues as templates was evaluated. A molecularly imprinted solid-phase extraction (MISPE) procedure was designed for the selective clean-up of maize extracts. Binding experiments and Scatchard analysis indicated the presence of specific binding sites in the imprinted polymers. The imprinting effect varied along with the selected template. The dissociation constant (K(D)) of the higher affinity binding sites ranged from 0.8 μmol/l to 15.6 μmol/l, while the K(D) of the lower affinity binding sites was in the range of 138.5-519.3 μmol/l. The performance of the MIPs throughout the clean-up of spiked maize sample extracts was evaluated and compared with the results obtained when applying a non-imprinted polymer. Depending on the polymers and the spiked concentration, recoveries after MISPE and non-imprinted solid-phase extraction varied respectively from 49% to 84% and from 28% to 31%. The imprinted polymers were superior regarding matrix effect, limit of detection (LOD) and limit of quantification (LOQ). LOD ranged from 0.17 μg/kg to 0.25 μg/kg and LOQ varied from 0.57 μg/kg to 0.82 μg/kg. Analysis of 15 maize samples by liquid chromatography tandem mass spectrometry revealed that the MIPs could be excellent sorbents for clean-up of contaminated food samples.     

A NOVEL MOLECULARLY IMPRINTED POLYMER： SYNTHESIS AND ADSORPTION BEHAVIOR OF GATIFLOXACIN

A kind of molecularly imprinted polymer （MIPs） with high selectivity was prepared using methacrylic acid （MAA） as functional monomer, ethylene glycol dimethacrylate （EDMA） as crosslinker and Gatifloxacin as template. The effect of various parameters such as volume of solvent, functional monomer dosage, crosslinker dosage and polymerization time were investigated. The selective binding experiment for substrates show that the affinity and selectivity for Gatifloxacin were higher than that for blank polymer. Scatchard analysis show that the MIPs recognized template with two kinds of binding sites. The dissociation constant Kd and maximum adsorption quantity Qmax of these two kinds of binding sites were calculated： Kd1 and Qmax1 of the binding sites with high affinity were 8.67×10^-4 mol/L and 28.19μmol/g, while Kd2 and Qmax2 of the binding sites with low affinity were 1.05×10^-3 mol/L and 33.20μmol/g respectively.     

Adsorption of carbaryl using molecularly imprinted microspheres prepared by precipitation polymerization

To obtain the desired specific adsorbents for carbaryl to enrichment, separation, and analysis of trace pesticide residues in environmental water, molecularly imprinted polymer (MIP) microspheres were prepared by precipitation polymerization using carbaryl, methacrylic acid (MAA), ethylene glycol dimethacrylate (EGDMA), azobisisobutyronitrile (AIBN), and acetonitrile as template, functional monomer, cross‐linker, initiator, and porogen, respectively. Molecular modeling software was used to compute rational interaction between the template molecule and function monomer. The adsorption properties of carbaryl in acetonitrile for imprinted microspheres were evaluated by equilibrium rebinding experiments. Scatchard plot analysis revealed that there was one class of binding sites populated in the imprinted polymer microspheres with dissociation constants of 3.3 × 10^?2 mol/l and an apparent maximum number of 1.95 µmol/g. The specificity of the imprinted microspheres was investigated by binding analysis using carbaryl and structurally related carbamate pesticides. The results indicated that the obtained imprinted microspheres showed a good selectivity for carbaryl. Copyright © 2007 John Wiley & Sons, Ltd.