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1.
分子印迹薄层色谱手性固定相的制备及其色谱性能   总被引:5,自引:0,他引:5  
戎非  李萍  冯小刚  袁春伟  付德刚 《色谱》2006,24(3):305-308
分别以右旋扁桃酸、右旋邻氯扁桃酸和右旋对氯扁桃酸为模板,丙烯酰胺、乙二醇二甲基丙烯酸酯为功能单体和交联剂合成分子印迹聚合物,并以此作为薄层色谱手性固定相。研究了模板分子消旋体在手性固定相上的分离情况,并讨论了展开剂中乙酸含量对分离的影响。在乙腈-5%乙酸展开体系中扁桃酸、邻氯扁桃酸和对氯扁桃酸消旋体得到较好的分离,分离因子分别为1.45,1.62和1.56。该手性固定相对模板分子的结构类似物也具有一定的手性交叉分离能力。讨论了分析物的化学结构对该手性固定相识别性能的影响。该方法为快速、灵敏地对手性物质分析、定性提供了一条简便的途径。  相似文献   

2.
李萍  李濬喆  林保平  戎非  袁春伟 《化学学报》2003,61(11):1885-1889
以混旋邻氯扁桃酸为模板分子和合成的(S)-(1-萘乙基)-丙烯酰胺为手性功能 单体制备分子印迹聚合物作为色谱固定相,对混旋邻氯扁桃酸有较好的拆分能力, 分离因子α达到1.36。但对模板分子的类似物混旋扁桃酸和对氯扁桃酸没有拆分能 力。用Hyperchem软件模拟了(S)-邻氯扁桃酸与(S)-(1-萘乙基)-丙烯酰胺形成的复 合物的结构模型,其在聚合物母体中留下的具有立体构型和作用力双重识别的S-S 型空穴,对(S)-邻氯扁桃酸有较强的保留作用,从而达到对混旋物拆分的目的。  相似文献   

3.
沉淀聚合法制备右旋邻氯扁桃酸分子印迹聚合物微球   总被引:15,自引:0,他引:15  
以右旋邻氯扁桃酸为模板,丙烯酰胺、乙二醇二甲基丙烯酸酯分别为功能单体和交联剂,采用沉淀聚合法制备了分子印迹聚合物微球,讨论了反应介质用量、聚合温度、引发剂的种类和用量对印迹微球的影响。实验表明:分子印迹微球与传统本体聚合法制备的聚合物相比具有更高的特异识别能力,通过Scatchard分析研究了聚合物的选择结合性能,结果表明分子印迹聚合物微球在识别右旋邻氯扁桃酸分子的过程中存枉两类结合位点,而空白聚合物微球只存在一类结合位点。  相似文献   

4.
王金朝  曾苏 《分析化学》2005,33(7):1050-1050
扁桃酸和邻氯扁桃酸是医药生产中的重要中间体。以氨基酸和金属离子作为手性流动相添加剂的配体交换色谱已被广泛应用于手性物质分离,但用于拆分扁桃酸较难,因其紫外吸收波长短,而使用最常用的Cu^2 作为配合离子时有很强的紫外吸收。本实验采用Zn^2 作配合离子,避开了检测方面的难题,直接拆分了扁桃酸和邻氯扁桃酸对映体。  相似文献   

5.
苯丙氨酸衍生物分子印迹聚合物的制备及手性拆分研究   总被引:5,自引:0,他引:5  
以分子印迹技术合成分子印迹聚合物,作为手性色谱柱的固定相来拆分苯丙氨酸衍生物的对映异构体。采用了新型的交联剂及光引发剂。模板分子和可聚合的功能单体形成配合物是分子印迹聚合物必不可少的条件。模板分子与功能单体的比例为1:4时,获得了良好的分离效果,分离因子α为1.69。光聚合方式合成的分子印迹聚合物比热聚合方式合成的拆分能力要高。且聚合的温度越低,聚合物分离效果越好。  相似文献   

6.
手性药物(S)-布洛芬氢键自组装印迹聚合物识别机理   总被引:3,自引:0,他引:3  
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.  相似文献   

7.
偶氮氯膦-DBF吸光光度法测定药物中铋   总被引:1,自引:0,他引:1  
在 0 .36mol·L- 1H2 SO4 0 .6 0mol·L- 1H3PO4 混合酸介质中 ,DBF 偶氮氯膦与铋形成蓝色配合物 ,最大吸收波长位于 6 38nm ,表观摩尔吸光系数为 9.4× 10 4 L·mol- 1·cm- 1,铋浓度在 0 30 μg/2 5ml范围内符合比耳定律。用直接光度法测定了果胶铋胶囊、陈香路白路片、枸橼酸铋钾颗粒等药物中铋 ,结果满意。  相似文献   

8.
在溴化十六烷基三甲基铵(CTMAB)存在下,Ti(Ⅳ)同甘露醇和邻苯三酚红在pH 3.4时形成蓝色的四元配合物,配合物的组成为n(Ti(Ⅳ))n(甘露醇)n(邻苯三酚红)n(CTMAB)=1123,配合物的最大吸收波长为630 nm,Ti在0~1.40μg/mL范围内符合比耳定律,摩尔吸光系数为3.1×105L·mol-1·cm-1.用抗坏血酸掩蔽Fe(Ⅲ),体系不需要分离可直接用于钢中微量钛的测定.  相似文献   

9.
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.  相似文献   

10.
邻氯基苯基荧光酮光度法测定食品中痕量铅   总被引:12,自引:0,他引:12  
研究了微乳液介质中,pH9.2时,铅与邻氯基苯基荧光酮(o CPF)显色生成稳定的1∶3配合物,在575nm波长处摩尔吸光率为5.5×104L·mol-1·cm-1,铅含量在0~1.4μg·ml-1范围内符合比耳定律,采用巯基葡聚糖凝胶分离富集,消除了共存离子的干扰。用所拟方法测定食品中微量铅,相对标准偏差在4.4%以下,加标回收率在95.5%~106.0%之间,结果满意。  相似文献   

11.
沉淀聚合法制备三聚氰胺分子印迹聚合物微球   总被引:7,自引:0,他引:7  
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.  相似文献   

12.
Summary Two molecularly imprinted polymers (MIP) have been prepared using the acidic drug salicylic acid, which can form intramolecular hydrogen bond, as the template and acrylamide or 4-vinylpyridine as the functional monomer. HPLC was used to evaluate the binding performance of the MIP for the template and for several analogues. The results showed that the MIP (P2) prepared using acrylamide as the functional monomer had no molecular imprinting effect whereas that (P1) prepared using 4-vinylpyridine as the functional monomer had a significant molecular imprinting effect. The reason the molecular imprinting effect was different for the two MIP was elucidated and the molecular recognition properties of P1 were studied in detail. It was confirmed that electrostatic interaction played an important role in the molecular recognition of P1. Scatchard analysis showed that two types of binding site with distinctly different affinity were formed in P1. Their dissociation constants were estimated to be 7.6×10−5 mol L−1 and 3.2×10−3 mol L−1, respectively. Because P1 has high affinity and selectivity for salicylic acid not only in organic systems but also in water-containing systems, it gives P1 the potential for use in the enrichment, separation, and detection of salicylic acid in biological fluids.  相似文献   

13.
硅基分子印迹技术制备铜离子选择电极   总被引:1,自引:0,他引:1  
以3-(2-氧基乙基氨基)丽基三甲氧基硅烷作为功能分子,铜离子为模板,将分子印迹技术与溶胶凝胶技术相结合,制备了铜离子选择电极,探讨了电极的响应机理.该电极对铜离子有较好的能斯特响应特性,其线性响应范围为5.00×10^-2~3.98×10^-6mol·L^-1,斜率为31.5mV/pC(-logc),检出限为1.00×10^-6mol·L^-1.同时该电极显示了较好的选择性,重现性和稳定性.  相似文献   

14.
A new molecularly imprinted polymer (MIP) was prepared using methamidophos (MAP) as the template molecule based on non‐covalent interaction. The complexes formed between template and monomers before polymerization were characterized by 1H NMR titration test, FT‐IR and UV spectrometry study. These studies indicated that a 1:2 molecular complex formed dominantly between MAP and functional monomers. A model mainly involving cooperative hydrogen interaction was proposed by exact placement of functional groups. Association constant was estimated to be 2.894 × 106 L2/mol2. When the initial concentration of MAP was 1.0 mmol L?1, the affinity capacity of MIP was 4.23 times that of NIP. The binding performance of MIP was modeled with the Freundlich isotherm (FI) and the total number of binding sites was calculated to be 33.97 μmol/g. The MIP showed great homogeneity with a heterogeneity index of m = 0.7356. The specificity of MIP was investigated by single‐analyte binding and molecularly imprinted solid‐phase extraction (MISPE) assays using MAP and other structurally related organophorous pesticides (OPPs). The results indicated that the MIP had a marked preference for MAP.  相似文献   

15.
单茂钛催化剂的丙烯无规聚合反应及其动力学研究   总被引:4,自引:1,他引:4  
比较了不同钛化合物/甲基铝氧烷(MAO)催化体系的丙烯无规聚合,催化活性次序为CpTi(OR)3>CpTi(OPh)3>CpTiCl3>Cp2TiCl2>Ti(OBu)4>TiCl4>Ti(OBu)2Cl2,所得聚丙烯用沸庚烷抽提8h,溶解95%以上,可溶部分经13C NMR、WADX、FTIR等分析证明为无规聚丙烯(aPP),是没有结晶性的弹性体.GPC测出其分子量Mw=8.0~10.0×104,Mw/Mn≈2.0.探索了催化体系CpTi(O n Pr)3/MAO中钛的浓度、[Al]/[Ti]摩尔比,丙烯聚合压力,聚合温度和时间对丙烯聚合反应的影响.研究了该催化体系丙烯聚合反应动力学规律,表观聚合反应速率对催化剂浓度和单体压力(浓度)都呈一级反应关系,表观聚合速率常数KP=292×105mol/L·h(40℃).活化能ΔE=-7.88×103J·mol-1,碰撞因子A=1.41×10-4mol/L·h.  相似文献   

16.
以Ni(COD)2和含磷、氧配体为催化剂,利用乳液聚合法合成了间规聚苯乙烯.对产物进行了13C-NMR、1H-NMR、GPC、TEM、DSC、TG等表征.在此反应体系下,最佳聚合条件为:乳化剂用量为1.50 g,[St]0=1.79 mol·L-1,T=60℃,t=2h,[Ni(COD)2]=1.102 mmol·L-...  相似文献   

17.
Yao J  Li X  Qin W 《Analytica chimica acta》2008,610(2):282-288
A computational approach was developed to screening functional monomers and polymerization solvents for rational design of molecularly imprinted polymer (MIP). It was based on the comparison of the binding energy of the complexes between the template and different functional monomers. The effect of the polymerization solvent was included using the polarizable continuum model. According to the theoretical calculation results, the MIP with aniline as template was prepared by emulsion polymerization method using acrylamide (AAM) as functional monomer and divinylbenzene as cross-linker in carbon tetrachloride. The synthesized MIP was then tested by equilibrium-adsorption method, and the MIP demonstrated high removal efficiency to the aniline. The results of this study have indicated the possibility of using computer aided design for rational selection of functional monomers and solvents capable of removal of aniline from contaminated water.  相似文献   

18.
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.  相似文献   

19.
以利巴韦林为模板分子,甲基丙烯酸为功能单体,采用沉淀聚合法制备利巴韦林分子印迹聚合物(MIP).以利巴韦林分子印迹聚合物掺杂氧化石墨烯(GO)为离子载体,聚氯乙烯为基质,癸二酸二辛酯为增塑剂制备电极敏感膜.结果表明,敏感膜组成为100.8 mg MIP、14.7 mg GO、450.8 mg聚氯乙烯和901.6 mg癸二酸二辛酯,内充液组成为0.1 mol/L NaCl+0.05 mol/L NaAc-0.05 mol/L HAc缓冲溶液+ 1.0×10.-5 mol/L利巴韦林,电极的响应性能最好.此电极的能斯特响应斜率为45.565 mV/decade,线性范围为1.0×10.-6~1.0×10.-4 mol/L, 检出限为1.0×10.-7 mol/L(S/N=3),工作pH范围为3~5,响应时间小于3 min.此电极对利巴韦林具有高选择性,可用于检测饲料和注射液中利巴韦林含量,加标回收率为90%~110%,RSD为3.0%~7.9%.  相似文献   

20.
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.  相似文献   

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