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1.
以白藜芦醇苷(POL)为模板分子,分别以丙烯酰胺(AM)、4-乙烯基吡啶(4-VP)、甲基丙烯酸羟乙酯(HEMA)、甲基丙烯酸(MAA)为功能单体,二甲基丙烯酸乙二醇酯(EGDMA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,采用本体聚合法制备白藜芦醇苷分子印迹聚合物。采用静态平衡结合实验研究了印迹聚合物对模板分子及不同底物的识别性能。结果表明,以丙烯酰胺为功能单体的印迹聚合物(MIP1)对模板分子的识别性能最好,其次是以4-VP为功能单体的聚合物(MIP2),以HEMA为功能单体的聚合物(MIP3)以及以MAA为功能单体的聚合物(MIP4)的分子识别性能较差。表明功能单体与模板分子之间相互作用的强弱对MIP的识别能力有较大的影响。静态平衡结合法以及Scatchard分析法表明,MIP1对模板分子呈现较好的结合能力和选择性,该印迹聚合物中形成了2类不同的结合位点,离解常数分别为7.43×10-5、3.70×10-3mol/L。将MIP1用于虎杖提取物中POL的固相萃取分离,效果良好。  相似文献   

2.
以白藜芦醇(RES)为模板分子,凹凸棒土(ATP)为载体,β-环糊精(β-CD)和甲基丙烯酸(MAA)为双功能单体,采用表面分子印迹技术制备了白藜芦醇分子印迹聚合物(MIPs)。将制得的分子印迹聚合物作为吸附剂填料,填充滤过型净化柱,用于富集净化花生根中的白藜芦醇,建立了分子印迹滤过型净化柱净化/分子荧光光谱测定花生根中白藜芦醇的新方法。在最优化条件下,分子印迹聚合物对RES具有良好的选择性,最大吸附容量可达12.78 mg/g,白藜芦醇在0.1~100μg/m L浓度范围内呈良好的线性关系(r=0.999 7),方法检出限为0.048μg/L,样品加标回收率为86.2%~102.1%,相对标准偏差(RSD)为3.5%~5.8%。该方法高效、快速、选择性好,可用于白藜芦醇的快速检测。  相似文献   

3.
以表面修饰乙烯基团的SiO2微球为基体,白藜芦醇为模板分子,丙烯酰胺(AA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,采用表面印迹技术制备核-壳型白藜芦醇印迹微球。采用红外光谱(IR)、扫描电子显微镜(SEM)对该分子印迹微球进行表征,结果表明,SiO2表面成功接枝一层厚度为200nm的印迹聚合物,该印迹微球颗粒分散均匀。采用高效液相色谱技术对印迹微球的吸附性进行研究表明,此印迹微球具有良好的识别性能,利用Scatchard模型分析得出印迹微球的最大吸附量分别为Qmax1=9.087mg/g和Qmax2=13.80mg/g。此印迹微球成功用于分离虎杖提取液中白藜芦醇。  相似文献   

4.
以反式白藜芦醇为模板分子,聚偏氟乙烯微孔滤膜为支撑膜,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸脂(EDMA)为交联剂,采用热引发原位聚合方法制备了白藜芦醇分子印迹聚合物膜。研究了分子印迹膜对白藜芦醇及其结构类似物(2-萘酚、白藜芦醇甙和双酚A)的结合和透过性,并用扫描电镜对膜形貌进行了表征。结果表明,印迹复合膜对模板分子白藜芦醇具有良好的吸附选择性,印迹膜对白藜芦醇的吸附量远远大于其它结构类似物,其饱和吸附量达1.72μmol/g,为非印迹膜的3倍;尺寸效应和印迹效应是影响物质在印迹膜上的透过量的两个重要因素,尺寸比模板分子小的2-萘酚最先透过,而相对于尺寸接近或大于模板分子的双酚A或白藜芦醇甙,模板分子优先透过。而且,模板分子在印迹膜上的透过量大于非印迹膜。  相似文献   

5.
制备了白藜芦醇的分子印迹聚合物,用聚四氟乙烯管作为微固相萃取柱,连接在流动注射系统的八通阀上,对白藜芦醇进行富集和分离;经甲醇和乙酸混合洗脱液(9:1,V/V)在线洗脱后与酸性KMnO4发生化学发光反应.测定白藜芦醇的线性范围2.5×10-7~6.1×10-5g/mL,方法的检出限为(3σ)8×10-8g/mL,11次...  相似文献   

6.
分子印迹技术研究进展   总被引:8,自引:0,他引:8  
分子印迹是制备具有分子特异识别功能聚合物的一种技术。本文从分子印迹聚合物的识别机理、分子印迹聚合制备条件和制备技术三个方面综述了分子印迹的研究进展,最后展望了分子印迹发展前景。引用文献66篇。  相似文献   

7.
磺胺二甲嘧啶分子印迹聚合物的合成及其识别性能   总被引:1,自引:0,他引:1  
磺胺二甲嘧啶分子印迹聚合物的合成及其识别性能;磺胺二甲嘧啶;分子印迹聚合物;硅胶;分子识别  相似文献   

8.
分子印迹技术是一种制备具有分子识别能力的聚合物的有效技术,已经广泛应用于制备对小分子具有选择性的分子印迹聚合物,但制备能够特异性识别生物大分子--蛋白质的分子印迹聚合物的研究仍然具有挑战性。本文讨论了制备蛋白质分子印迹聚合物的难点,评述了目前印迹蛋白质的方法及各自的优缺点,展望了蛋白质印迹技术的发展趋势。  相似文献   

9.
分子印迹电化学传感器能够选择性识别并检测特定目标化合物,因其设计简单、灵敏度高、价格低廉、携带方便、易于微型化和自动化等优点,在临床诊断、环境监测、食品分析等方面越来越受到人们的关注.本文作者主要论述分子印迹技术与电化学技术相结合构建分子印迹电化学传感器,包括分子印迹电化学传感器的种类,以及电化学方法制备分子印迹聚合物膜的常用单体等.对分子印迹电化学传感器领域新出现的分子印迹聚合物-纳米材料复合物以及纳米结构分子印迹聚合物也一并做了评述.  相似文献   

10.
热聚合制备左氧氟沙星分子印迹聚合物的分子识别特性   总被引:1,自引:0,他引:1  
热聚合制备左氧氟沙星分子印迹聚合物的分子识别特性;左氧氟沙星;分子印迹聚合物;Scatchard分析;热力学  相似文献   

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Lanthanide reducing agents have been found to effectively promote intramolecular alkylation reactions to provide the corresponding bicyclic alcohols in excellent yields.  相似文献   

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A series of isomeric fully aromatic polyamides (aramids) were photodegraded in the presence of oxygen. Films and fibers of these aramids gave carboxylic acids as the major products when measured by infrared spectroscopy and potentiometric titration. These acids probably resulted from the oxygen interception of the radicals generated by photocleavage of the amide bonds. In contrast to results found upon irradiation in the absence of oxygen, carboxylic acid formation was accompanied by a rapid loss in molecular weight, and a decrease in useful mechanical properties. Quantum yields for carboxylic acid formation were ≤5.5 × 10?5 mole/einstein and decreased along the aramid series roughly in agreement with increases in Tg. The photo-Fries rearrangement product was observed in aramid fibers irradiated in air, whereas no rearrangement product was seen in films irradiated in air.  相似文献   

17.
The cadmium content of the I.A.E.A Fish Solubles [A-6 (1975)] was determined by the isotope dilution method. After dry-ashing and dissolution of the specimen, the cadmium was equilibrated with a known amount of 103Cd spike, isolated by ion exchange, purified by dithizone extraction, and converted to the sulfide form in 1% H3PO4 solution. The CdS precipitate was loaded onto a baked single rhenium filament for mass spectrometric analysis. The 103Cd/110Cd ratio was measured to compute the cadmium content of 0.278 ± 0.032 ppm (dry weight basis) in the Fish Solubles.  相似文献   

18.
The title compound, [cis-Co(en)2(NO2)2](NO2) (1), crystallizes in the polar, nonenantiomorphic, monoclinic space group, Cc, with lattice constants:a=9.198(2) Å,b=12.444(2),c=9.963(3), and=96.76(2)°;V=1132.39 Å3 andd(calc;Z=4) =1.860 g cm–3. Thus, with NO2– as the counteranion, [cis-Co(en)2(NO2)2] crystallizes in a heterochiral lattice containing racemic pairs of cations. A total of 2699 data were collected over the range of 4°270°; of these, 1859 (independent and withI3(I)) were used in the structural analysis. Data were corrected for absorption (=15.465 cm–1) and the relative transmission coefficients ranged from 0.9934 to 0.7112. Refinement was carried out for both lattice polarities and the finalR(F) andR w (F) residuals were, respectively, 0.0242 and 0.0202 for (–––) and 0.0264 and 0.0243 for (+++). Thus, the former was selected as correct for our specimen.Unlike all previous X-ray diffraction studies of the structural properties of the cation [cis-Co(en)2(NO2)2]+, which are found to have a pair of oppositely configured en rings [i.e., () or ()], we find that in1 the cations are in the lowest energy conformation and configuration; i.e., () or (). We attribute this change in configuration to the formation of strong interionic hydrogen bonds between nitrite anion oxygens and the axial—NH2 hydrogens, which markedly weaken the intermolecular and intramolecular hydrogen bonds between ligand—NO2 oxygens and the hydrogens of those same amine moieties. Thus, the nitrite anions behave exactly as nitrate anions, except that the hydrogen bonds found here are stronger than those formed by the latter. This is as expected since the negative charge is delocalized over two, instead of three, oxygens.  相似文献   

19.
The proton n.m.r. spectra of lipids containing triglycerides and wax esters dissolved in CDCl3 are characterized by seven sets of signals. The areas of the signals of terminal methyl group and of methylene protons of both wax ester and triglyceride were integrated. These were used to calculate the content of wax esters in lipids or oils. The rapid n.m.r. procedure is directly usable for natural lipids containing as low as 3 mg of wax esters in 50-mg samples with an error of about 7%. The method described compares favorably with t.l.c. determination.  相似文献   

20.
Near-U.V. photolysis of pyrimidine heteroadducts in E. coli DNA   总被引:1,自引:0,他引:1  
Abstract— The cytosine-thymine precursor of the U–T adduct is not subject to enzymatic photoreactivation, but can be eliminated directly from u.v.-irradiated E. coli DNA by exposure to wavelengths around 313 nm.  相似文献   

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