硝酸铵水凝胶分子印迹聚合物的制备

目的:目前安全问题成为世界各国的首要问题,尤其是对炸药分子的检测。硝酸铵是硝铵炸药的主要成分。研究水凝胶分子印迹法对硝铵炸药分子的检测。方法:水凝胶分子印迹方法制备硝酸铵水凝胶分子印迹聚合物,运用静态结合实验对其结合率进行了测定。结果:聚合物对硝酸铵具有良好的识别和吸附性能。印迹聚合物的解离常数为4.08g/L,最大吸附量为3.51mg/g。结论:水凝胶分子印迹法可合成水溶性炸药分子印迹聚合物,并且识别及吸附性能良好。     

核壳型离子印迹聚合物的制备与应用

离子印迹聚合物(IIPs)是利用分子印迹技术对目标离子进行印迹、聚合进而得到对模板离子有选择性吸附的聚合物。核壳型离子印迹聚合物作为一种新型吸附材料被应用于样品的处理和实际检测中。本文对核壳型离子印迹聚合物的核壳类型、印迹聚合物的制备方法及实际检测应用等最新研究进展进行综述,为核壳型离子印迹聚合物的研究与应用提供参考。     

白藜芦醇分子印迹聚合物微球的制备及特性评价(英文)

以聚苯乙烯微球为种球,白藜芦醇为模板分子,采用单步溶胀聚合法在N,N-二甲基甲酰胺体系中制备了单分散分子印迹聚合物微球。用扫描电镜对微球的结构和形貌进行了表征,并研究了微球的制备条件和吸附特性。微球的凹陷可有效地增加微球的比表面积和结合位点,从而提高了模板分子的结合速率及微球的印迹容量。     

分子印迹技术研究新进展

分子印迹技术是在近十几年来才发展起来的一门边缘科学技术。它结合了高分子化学、生物化学等学科 ,是模拟抗体 -抗原相互作用的一种新技术 ,具有选择性识别位点的性质。现已应用于色谱分离、抗体和受体模拟物、固相萃取、生物传感器等领域。     

量子点表面分子印迹光纤传感器的制备及应用

近年来,许多研究人员不断努力为药物、除草剂、食品添加剂等小分子物质高特异性、高灵敏的检测和分析开发新的方法和技术。然而,目前通用的分子检测方法的实施需要较长的前处理时间、昂贵的大型仪器设备及专业操作人员,无法实现有选择的识别及快速的现场检测。所以,在本研究中我们将量子点表面分子印迹聚合物(QDs@MIPs)与光纤相结合,构建了一种新的光纤探头,并将该光纤探头应用于光纤传感器,检测小分子物质莱克多巴胺(RAC)。试验中,我们对QDs@MIPs的表征、光纤探头的性能、光纤探头对RAC的浓度响应、光纤传感器的特异性及光强分布进行了探究。研究结果表明,该光纤探头应用于光纤传感器能够提高光纤传感器的灵敏度,使分子印迹光纤传感器具有更高的特异性识别能力和较强的抗干扰能力,同时检测过程简便快捷,适用于快速的现场检测。     

分子印迹聚合物对血浆中异丙酚吸附的研究

目的：合成异丙酚分子印迹聚合物,并用聚合物萃取人血浆中的异丙酚。方法：用热聚合法制备异丙酚分子印迹聚合物,考查聚合物的性能,并用它来萃取血浆中不同浓度的异丙酚。结果：模板分子和功能单体以氢键的方式结合;分子印迹聚合物选择性地吸附血浆中的异丙酚。结论：分子印迹聚合物可以从人血浆中吸附异丙酚,其吸附率受底物浓度的影响。     

恩诺沙星分子印迹电化学传感器的制备及其在食品快速检测中的应用

以恩诺沙星(ENRO)为模板分子,邻苯二胺(OPD)和邻氨基苯酚(OAP)为复合功能单体,在NaAc-HAc缓冲液中,采用电聚合法在玻碳电极表面制备了能够特异识别模板分子及其结构类似物的分子印迹电化学传感器。试验选用含1mol/L氯化钾及1mmol/L铁氰化钾的混合液作为表征溶液,采用循环伏安法和方波伏安法研究了传感器的电化学响应特性,并优化制备和检测条件。结果表明,在最佳条件下,恩诺沙星在2×10~(-6)mol/L～4×10~(-5)mol/L浓度范围内线性关系良好,检出限为7. 0×10~(-7)mol/L,该传感器具有良好的稳定性和重现性,对恩诺沙星以及结构类似物具有良好的选择性。采用该传感器对实际样品牛奶、鸡肉、猪肉和鸡蛋中的恩诺沙星进行检测,加标回收率在83. 2%～92. 7%之间,相对标准偏差(RSD)在1. 0%～4. 8%之间(n=5),该传感器选择性强、稳定性好、操作简便、检测快速灵敏、成本低、具有良好的应用前景。     

DNA水凝胶的制备及应用

脱氧核糖核酸(Deoxyribonucleic acid,DNA)不仅可作为生物遗传的物质基础,又以其可编程性、功能多样性、生物相容性和生物可降解性等优点,在生物材料的构建方面表现出巨大的潜力。DNA水凝胶是一种主要由DNA参与形成的三维网状聚合物材料,同时因其保留的DNA生物性能与自身骨架的机械性能的完美融合使得它成为近年来最受关注的新兴功能高分子材料之一。目前,基于各种功能核酸序列或通过结合不同的功能材料制备的单组分或多组分DNA水凝胶,已广泛用于生物医学、分子检测及环境保护的研究或应用领域中。文中主要总结了近十几年来DNA水凝胶制备方法上的研究进展,探讨了DNA水凝胶的分类策略,并进一步综述了DNA水凝胶在药物运输、生物传感、细胞培养等方面的应用研究。最后对DNA水凝胶未来的发展方向以及可能面临的挑战进行了展望。     

分子印迹技术用于生物大分子的识别

分子印迹技术是一种人工合成具有分子识别功能的介质的一种新技术,近年来在许多领域都得到很大的发展。本文介绍了分子印迹技术的发展现状,尤其对生物大分子的分子印迹技术进行了详细论述,对生物大分子印迹采用的功能单体,印迹分子的种类,印迹的方法,印迹的机理,存在的问题和应用的前景等分别进行了讨论。     

分子印迹技术应用于血清中地高辛的快速检测

应用分子印迹的方法制备对地高辛有特异性吸附性能的印迹聚合物颗粒,再将颗粒与琼脂糖混合并固定于玻碳电极上制备成地高辛分子印迹聚合膜传感器,传感器可以特异性地结合模板分子地高辛且其电化学信号与模板浓度相关,再用它来检测血清中地高辛的含量。结果表明:分子印迹传感器具有制作简便、成本低、检测快速、特异性高、稳定性好等优点,检测下限为1.28 nmol/L,检测时间为5 min。     

Molecularly imprinted polymer films for reflectometric interference spectroscopic sensors

Reflectometric interference spectroscopic measurements were performed on molecularly imprinted polymer (MIP) films with the herbicide atrazine as the template molecule. A conventional imprinting protocol was used relying on non-covalent interactions between the functional monomers and the template. The MIPs were deposited on glass transducers by two different methods: spin-coating followed by in situ polymerization of thin films of monomers containing a sacrificial polymeric porogen, and autoassembly of MIP nanoparticles with the aid of an associative linear polymer. Reproducible results were obtained upon measurements of atrazine solutions in toluene with both films. Atrazine concentrations as low as 1.7 ppm could be detected with the autoassembled particle film. No or very little analyte adsorption was observed onto non-imprinted control films made by spin-coating and by particle assembly, respectively. We believe that these MIP layers in combination with the general reflectrometric transduction scheme could be a versatile sensing tool for the detection of environmentally important and other analytes.     

Optimizing the formulation of a myoglobin molecularly imprinted thin-film polymer--formed using a micro-contact imprinting method

Thin-film myoglobin molecularly imprinted polymers have been fabricated using a micro-contact approach. By initially selecting the cross-linker on the basis of it having a minimal recognition for the template and using this as a starting point for functional monomer selection, we have produced myoglobin imprinted polymers with exceptionally high selectivities.

The affinity of the polymers, for myoglobin, when prepared with a variety of different cross-linkers and no functional monomer was evaluated. Of these, tetraethylene glycol dimethacrylate (TEGDMA) exhibited the lowest affinity for the template species. Methyl methacrylate (MMA) was chosen as the functional monomer as when it was used in conjunction with TEGDMA, it exhibited maximum selectivity for the template compared to polymers made with other functional monomers.

With a MMA to TEGDMA ratio of 1 to 3, the myoglobin molecularly imprinted polymer adsorbed 15.03 ± 0.89 × 10⁻¹¹ mole/cm² of template from a 5.68 × 10⁻⁷ M myoglobin solution, compared to 2.58 ± 0.02 × 10⁻¹¹ mole/cm² for a polymer of similar composition, but formed in the absence of a template. Various washing conditions, using alkaline media to remove the template, were investigated. An extraction solvent comprising 2 wt.% SDS and 0.6 wt.% NaOH used at 80 °C for 30 min was shown to give the highest imprinting factor i.e. 5.83 with 72.82% myoglobin removal.

The saturation kinetics of template binding to the thin-film MIP were examined and found to display a simple two-phase profile typical of non-cooperative binding. A Scatchard binding plot showed the dissociation constant (K_d) for the specific binding phase to be 3.4 × 10⁻⁷ M and the binding site capacity to be 7.24 × 10⁻¹¹ mole/cm². For the non-specific binding phase, K_d was found to be 1.355 × 10⁻⁵ M and the binding site capacity was determined as 9.62 × 10⁻¹⁰ mole/cm².

Selectivity experiments were carried out in both single protein and binary protein systems all using a total protein concentration of 5.68 × 10⁻⁷ M. The molar ratio of adsorbed myoglobin to IgG, HSA and hemoglobin was found to 115.5, 230.9 and 2.5, respectively. While, in binary competition systems, myoglobin selectivity to IgG, HSA and hemoglobin was, respectively, 94.18, 98.21 and 61.09%. Rebinding in natural biological matrices, i.e. human serum or urine, showed the imprinted films to have significantly greater uptake than non-imprinted films. Re-binding in undiluted urine was found to be a facile process, with the imprinting factor, i.e. the ratio of MIP to NIP binding, being determined as 37.4.     

The Selective Detection of Cyantraniliprole Insecticides Using Molecularly Imprinted Polymers Coupled with an Acetylcholinesterase Inhibition-Based Biosensor

Cyantraniliprole is one of the anthranilic diamide insecticides widely used in the agriculture sector. Due to its low toxicity and relatively fast degradation, there is need for a sensitive determination method for its residues. Nowadays, there is growing interest in the development of enzyme-based biosensors. The major drawback is the non-specific binding of many insecticides to the enzyme. This work employs Molecularly imprinted polymers (MIPs) to increase enzyme specificity and eliminate the organic solvent effect on the enzyme activity. The synthesized Cyan-Molecularly imprinted polymers (Cyan-MIP) possesses high affinity and selectivity toward cyantraniliprole. Acetylcholinesterase assay characteristics including enzyme concentration, substrate concentration, DTNB concentration, and acetonitrile concentration were optimized. Under optimal experimental conditions, the developed MIP-Acetylcholinesterase (MIP-AchE) inhibition-based sensor provides better precision than the AchE inhibition-based sensor with a wide linear range (15–50 ppm), limit of detection (LOD) 4.1 ppm, and limit of quantitation (LOQ) 12.6 ppm. The sensor was successfully applied for cyantraniliprole determination in spiked melon, giving satisfactory recoveries.     

Preparation and evaluation of a molecularly imprinted polymer for the selective recognition of testosterone--application to molecularly imprinted sorbent assays

Biomimetic testosterone receptors were synthesized via molecular imprinting for use as antibody mimics in immunoassays. As evaluated by radioligand binding assays, imprinted polymers prepared in acetonitrile were very specific for testosterone because the nonimprinted control polymers bound virtually no radiolabeled testosterone. The polymers present an appreciable affinity, with association constants of K(a) = 3.3 x 10(7) M(- 1) (high-affinity binding sites). The binding characteristics of the polymers were also evaluated in aqueous environment to study their viabilities as alternatives to antibodies in molecularly imprinted sorbent assays. Compared with the testosterone-specific antibodies present in commercial kits, our molecularly imprinted polymers are somewhat less sensitive but show a high selectivity.     

Molecularly imprinted polymer-assisted sample clean-up of ochratoxin A from red wine: merits and limitations

A new analytical method for the determination of the carcinogenic mycotoxin ochratoxin A (OTA) in red wines has been developed involving a two-dimensional solid-phase extraction (SPE) clean-up protocol on C18-silica and a target-selective molecularly imprinted polymer (MIP). Prior removal of the interfering acidic matrix compounds by C18 solid-phase extraction was crucial for a successful clean-up as direct sample loading onto the MIP led to poor recoveries. The combined solid-phase extraction protocol afforded extracts suitable for sensitive ochratoxin A quantification by HPLC-fluorescence detection. Preliminary validation of the method performance with spiked (0.033-1.0 ng OTA/ml) and commercial red wines provided recoveries >90% and < 10%, with limit of detection (LOD) and limit of quantification (LOQ) of 0.01 and 0.033 ng/ml. However, a similarly favorable performance characteristics was observed in control experiments in which the MIP was replaced by the corresponding non-imprinted polymer (NIP). These findings provide evidence that under the employed experimental conditions specific analyte binding to imprinted binding sites plays a minor role in selective OTA retention. In the framework of this study, other problems inherent to MIP-based solid-phase extraction have been addressed. These include the reproducible preparation of MIP materials with consistent molecular recognition characteristics, the potential for repeated use of MIP, unfavorable polymer swelling in application-relevant solvents, potential sample contamination by template bleeding, and slow analyte binding kinetics.     

蔗糖和硝酸铵对黄连悬浮培养细胞生长和小檗碱含量的影响

在６、７－Ｖ液体培养基中较为适合黄连细胞生长的蔗糖浓度为．３％,当蔗糖浓度增加到７％时,细胞生长速率开始下降,但小檗碱含量提高到５．２０％．小檗碱产率为４５６．６０ｍｇ／Ｌ（２３天）。基本培养基中随着补加ＮＨ４ＮＯ３浓度的增加,抑制细胞生长愈严重;补加０．８ｇ／ＬＮＨ４ＮＯ３的小檗碱含量比未加的增加约１０％,随着浓度的增加又急剧下降。     

基于分子印迹技术的细菌传感检测

分子印迹因其材料结构的稳定性及靶标物识别的特异性而被广泛应用于生化分离分析的相关领域。近年来，将具有选择性捕获、分离和富集靶标物等优势的分子印迹技术与生化传感检测技术有机结合，是目前细菌等微生物高效检测领域备受关注的研究热点。本文就分子印迹技术在细菌分析中的印迹方法、分析检测技术和典型应用等方面的最新进展进行综述。首先介绍了细菌分子印迹原理，对表面印迹的材料以及直接压印、间接印迹和电聚合等制备方法进行了总结和归纳；重点对基于荧光、电化学、石英晶体微天平（QCM）等检测模式的细菌印迹传感监测在细菌分析检测及其与微流控芯片技术耦合的应用和进展进行了综述；最后，提出了存在的挑战及发展的趋势。