牛血清白蛋白在超薄纳米二氧化钛膜表面的印迹与吸附

基于溶胶凝胶分子印迹方法,以溶胶二氧化钛TiO2为基质印迹了牛血清白蛋白分子。用1%的NaOH溶液可有效地除去纳米TiO2印迹膜中的模板分子。采用石英晶体微天平现场技术,研究了牛血清白蛋白在超薄纳米TiO2膜表面的吸附行为。研究表明,牛血清白蛋白在印迹膜和非印迹膜上的吸附量都随溶液浓度增加而增大,印迹膜具有吸附的特异性和可再生性,其吸附量是非印迹膜的3~5倍;在非印迹膜上的吸附符合Langmuir吸附模型,而在印迹膜上的吸附符合allosteric吸附模型;牛血清白蛋白在非印迹膜上的吸附量先随pH升高而增大,当pH为5左右时达到最大值,随后吸附量又随pH的增大而减小;而在印迹膜上其吸附量仅随pH增大而增大。     

基于分子印迹技术的牛血清白蛋白电位式传感器的研究

以牛血清白蛋白(BSA)为模板,合成了分子印迹聚合物凝胶(MIP),进而制得了以聚氯乙烯(PVC)为支撑膜的BSA电位式传感器。采用直接电位法测得BSA在浓度0.1～1.0 mg/mL范围内与电位呈线性关系。此电极制作简单,可用于BSA的测定。     

白藜芦醇分子印迹复合膜的制备及其选择性能

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。     

Use of poly(ethylene terephthalate) track membranes as template matrices for the preparation of polymeric nanomaterials based on polypyrrole and poly(<Emphasis Type="Italic">N</Emphasis>-methylpyrrole)

The oxidative polymerization of pyrrole and N-methylpyrrole with the use of template synthesis on poly(ethylene terephthalate) (PET) track membranes was studied. By scanning electron microscopy (SEM), it was found that a polymer film was formed on the surface of membranes and on the walls of membrane pores. The rates of polymerization on the surface of membranes and pore walls, as well as the yield and structure of the polymer film, depend on the membrane parameters (pore length and diameter and membrane porosity), the chemical structure of the monomer, the diffusion of polymerized solutions through template pores, and the temperature.Translated from Khimiya Vysokikh Energii, Vol. 39, No. 1, 2005, pp. 15–20.Original Russian Text Copyright © 2005 by Dobretsova, Ermolaev, Jitariouk, Milinchuk.     

牛血清白蛋白Langmuir膜控制方解石形成取向生长的球形微晶

本文以生物矿化模型系统为基础，利用LB技术，采用本体交换的方法，制备了牛血清白蛋白(BSA)Langmuir膜，以更加接近生物矿化的方法研究了BSA Langmuir膜对碳酸钙晶体生长的取向、形貌和晶型的控制作用。XRD分析表明晶体为碳酸钙的方解石晶型，且晶体仅沿(104)晶面有取向生长。SEM分析表明结晶初期碳酸钙以球状的晶体存在，随着时间的延长，BSA对晶体形貌的控制作用逐渐减弱，直到完全不起作用，在结晶后期形成菱方形晶体，但晶体生长取向和晶型始终没有发生变化。说明BSA Langmuir膜对碳酸钙的生长取向、晶型和形貌有较好的控制作用。     

Novel nylon-supported organic-inorganic hybrid membrane with hierarchical pores as a potential immobilized metal affinity adsorbent

Chitosan-based porous organic-inorganic hybrid membranes supported by microfiltration nylon membranes were prepared, in which gamma-glycidoxypropyltrimethoxysilane (GPTMS) was used as an inorganic source as well as crosslinking reagent. Polyethylene glycol (PEG) with different molecular weight and content was used as imprinting molecule for morphology control. In situ crosslinking of chitosan and simultaneous polymerization of GPTMS in PEG template environment endowed the hybrid membrane with specific characteristics. Distinct hybrid effect between chitosan (CS) and GPTMS was revealed by shifting in X-ray diffraction (XRD) pattern, decomposition in simultaneous thermogravimetry and differential scanning calorimetry (TG/DSC) testing. As manifested by scanning electron microscopy (SEM), the molecular weight and content of PEG had remarkable effect on the resulting surface morphology of the hybrid membrane and a given surface morphology could be obtained by extracting of the imprinted PEG molecular. Among three types of porogen used: PEG 400, PEG 4000 and PEG 20000, only PEG 20000 could result in a porous surface. Moreover, a special porous surface with three-dimensional (3D) hierarchical structure-in-structure pore fashion was obtained when content of PEG 20000 was controlled at 15%. Experimental results also showed that the hybrid membrane had low swelling ratio and high stability in acidic solution. After conveniently coordinated with copper ions, the porous metal chelating hybrid membrane could effectively adsorb the model protein, bovine serum albumin (BSA). As expected, the hybrid membrane imprinted with 15% PEG 20000 had remarkably high copper ion binding and BSA adsorption capacity, which might result from the large surface area, high ligand density and suitable interconnected 3D hierarchical porous surface.     

Preparation and Characterization of PVDF‐HFP Membrane

Poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) microporous membrane was prepared by supercritical CO₂ extraction of dibutyl phthalate (DBP) template from PVDF‐HFP/DBP film. The effects of extraction conditions such as pressure, temperature, and extraction time on extraction efficiency and the porosity of membrane were studied. The extraction efficiency of DBP and size stability of polymer membrane during extraction was compared with those of solvent extraction process. The structure of the resulting membrane was characterized by scanning electron microphotograph (SEM), X‐ray diffraction (XRD) and differential scanning calorimeter (DSC). With increasing the extraction temperature, pressure and time, the extraction efficiency and the porosity increased. Maximum extraction efficiency is obtained at extraction pressure and temperature higher than 18 MPa and 75°C, respectively. The porosity of membranes depended on the extraction efficiency and shrinkage ratio of membranes. Compared with solvent extraction, supercritical CO₂ extraction of the film generated the membrane with more uniform structure and higher porosity.     

基于荧光增强效应的可逆型牛血清白蛋白光化学生物传感器研究

研究了一种具有可逆响应的蛋白质生物传感器。敏感层由丙烯酰胺荧光素固定于硅烷化的平面波导上形成，然后装配在自制的流通池中并用光导纤维连入荧光分光光度计，结果发现牛血清白蛋白（BSA）对此敏感膜有明显的荧光增强反应，在0.4-20μmol/L范围内敏感膜的荧光增强度与BSA的浓度呈线性关系，检测下限为0.1μmol/L。并且此传感器无需特殊的试剂及其进行再生，等电点不同的蛋白质引起的荧光增强程度也不同，常见的金属离子对测定无影响，但重金属离子对测量有较大的影响。对传感器的响应机理也进行了多方面的分析，推测传感器的响应可能是由蛋白质上的氨基与丙烯酰胺荧光素上的羧基发生反应引起的。     

牛血清白蛋白LB膜诱导方解石的生长

采用模拟生物矿化的方法,研究了牛血清白蛋白(BSA) LB膜对碳酸钙晶体成核和生长的诱导控制作用。XRD、SEM结果表明：在BSA单层LB膜诱导下,形成形状规则、边缘清晰的多层盘状方解石晶体,且沿(104)晶面取向生长。说明牛血清白蛋白(BSA) LB膜对碳酸钙的形貌、生长取向性有很好的调控作用。     

蛋白质分子印迹聚合物研究

分子识别现象在生命过程中扮演着极其重要的角色,对此进行研究和探索是化学和生物学领域的核心课题,制备具有分子识别能力的人工受体是对该领域科学工作者的一个持久挑战．为此,相关研究人员进行了多方努力,创造性地发展了许多崭新的方法和手段,其中的分子印迹聚合物制备技术就是这些方法和手段中的一种.     

分子印迹壳聚糖膜和柚皮苷模板分子间相互作用的研究

以壳聚糖为膜材料,以柚皮苷为模板分子,通过硫酸交联在水相中制备了水相识别柚皮苷分子印迹壳聚糖膜。通过高效液相色谱（HPLC）、紫外光谱（UV）和红外光谱（FT-IR）初步研究了模板分子和功能单体之间的相互作用,表明体系产生了新的氢键。     

Adsorption behavior of metal ions onto a bovine serum albumin (BSA) membrane monitored by means of an electrode-separated piezoelectric quartz crystal.

The interaction between metal ions and bovine serum albumin (BSA) was studied by using a piezoelectric quartz crystal (PQC) arranged in the electrode-separated configuration. A silanized surface of the PQC was coated with a BSA membrane via a coupling reaction with glutaraldehyde. The frequency shifts obtained from PQC coated with a BSA membrane suggested that various kinds of metal ions could be adsorbed onto the BSA membrane from aqueous solutions containing a low concentration of metal ions (2 or 10 micromol dm(-3)), only when the BSA was denatured with an alkaline solution. Anionic species of Pt(IV) and Au(III) were adsorbed onto the denatured BSA membrane from an acetic acid solution at pH 2.2, and cationic species of Cd(II), Zn(II), Co(II), Ni(II), Cu(II), and Ag(I), and cations, such as Ca2+, Ba2+, and Mg2+, were adsorbed from ammonia buffer at pH 9.5, whereas Al(III), Cr(III), Fe(III), Hg(II), and Pb(II) were hardly adsorbed. The adsorption mechanisms of these metal ions are discussed, based on the electrostatic interaction between the metal ions and the denatured BSA membrane, and complex formation between the metal ions and amino acid residues of the denatured BSA. Further, the PQC coated with a denatured BSA membrane was applied to the determination of Pt and Cd, using large frequency shifts for Pt(IV) and Cd(II).     

牛血清白蛋白和溶菌酶为双模板蛋白质的表面印迹聚合物的制备及吸附性能

采用反应条件温和的原子转移自由基聚合法(ATRP),以N-异丙基丙烯酰胺(NIPAAm)和丙烯酰胺(AAm)为功能单体,以N-(3-二甲氨基丙基)甲基丙烯酰胺(DMAPMA)为辅助功能单体,制备了以牛血清白蛋白(BSA)和溶菌酶(Lyz)为双模板蛋白质的表面印迹聚合物(Bi-MIP)。对印迹过程中辅助功能单体的量进行了考察,结果表明,在单一蛋白质溶液和混合蛋白质溶液中,当DMAPMA为20 μL时,制备的Bi-MIP对模板蛋白质BSA和Lyz有较好的吸附容量与选择性。通过静态吸附实验考察了Bi-MIP的吸附性能,并结合Langmuir吸附模型得到聚合物对模板蛋白质BSA和Lyz的最大吸附容量分别为10.2 mg/g和19.2 mg/g。且该印迹聚合物在实际样品中对模板蛋白质也表现出较强的吸附能力和较高的选择性。该方法将为复杂生物样品中同时对双/多种目标蛋白质的识别提供一种新的途径。     

香豆素-3-羧酸分子印迹聚合物复合膜对底物的结合及渗透选择性质的研究

在光照和引发剂的作用下, 模板分子香豆素-3-羧酸、 功能单体丙烯酰胺和交联剂乙二醇二甲基丙烯酸酯(EDMA)或三甲氧基丙烷三甲基丙烯酸(TRIM)在聚偏氟乙烯(PVDF)微孔滤膜表面聚合形成分子印迹聚合物复合膜. 用高效液相色谱仪测定了分别以TRIM和EDMA为交联剂制备的分子印迹聚合物膜在不同溶剂中对混合底物的结合和渗透选择性. 结果表明, 以TRIM为交联剂的印迹膜对模板分子具有更高的结合和渗透选择性. 另外, 以乙腈或乙腈/水作为溶剂对分子印迹膜所作的实验和讨论有助于为从复杂样品中分离模板分子奠定理论和实验基础.     

A facile route to fabrication of inorganic-small organic molecule cable-like nanocomposite arrays

A novel and facile method is reported for the preparation of silver iodide-small organic molecule (SOM) cable-like nanocomposites arrays, which involved first the fabrication of SOM nanotubes inside an anodic aluminium oxide (AAO) membrane, and then using the SOM nanotubes in AAO as secondary template to prepare the AgI nanowires in aqueous solution at room temperature.     

Embedding of individual ferritin molecules in large, self-supporting silica nanofilms

We report herein the fabrication of ferritin-embedded self-supporting silica nanofilms via a simple spin-coating process. Ferritin was employed as a template molecule, and solutions of ferritin and silica were spread on a polymer-coated silicon substrate, in this order. After dissolving the polymer underlayer by simply immersing ethanol, a centimeter-sized self-supporting nanofilm of ferritin/silica composite with a thickness of 15 nm was successfully transferred onto an alumina membrane without the film breaking. Ozone and hydrochloric acid solution treatment removed the template ferritin molecules from the composite film to produce corresponding transmembrane nanoholes. The reported method is very simple, and the fabrication of a protein-embedded self-supporting nanofilm enables the design of biomembrane-mimetic devices.     

The Rebinding Properties of Bovine Serum Albumin Imprinted Calcium Alginate/Phosphate Hybrid Microspheres Via the Adjustment of pH Values and Salt Concentration

Summary: Bovine serum albumin imprinted calcium phosphate/alginate hydrogel microspheres were prepared with sodium alginate (SA), (NH₄)₂HPO₄, and using CaCl₂ as gelling agent, bovine serum albumin (BSA) as template in inverse suspension. The optimized rebinding properties of BSA imprinted hydrogel microspheres were investigated by controlling pH value and ionic concentration from the viewpoint of adjusting the process of gelling, removing template and rebinding. The optimized pH values for the imprinting of BSA in gelling, removing template and rebinding process was 4.1, 8.3 and 4.8, respectively. The effect of NaCl concentration on the BSA rebinding was also determined. We provided a strategy to get the optimized imprinting efficiency by altering pH value and ionic concentration in a weakly ionic cross-linked hydrogel system on the process of protein's imprinting.     

Electrochemically deposited nanocomposite of chitosan and carbon nanotubes for detection of human chorionic gonadotrophin

A new label-free amperometric immunosensor was developed for detection of human chorionic gonadotrophin (hCG) based on multiwall carbon nanotubes-chitosan (MWNTs-CS) complex film and three-dimensional AuNPs-TiO(2) hybrid. Firstly, MWNTs-CS film was deposited on a glassy carbon electrode (GCE) by a simple and controllable electrodeposition method. Next, thionine (Thi), as a redox probe, was covalently bound onto the MWNTs-CS film with glutaraldehyde (GA) to obtain the Thi/MWNTs-CS film. The free amino groups of the composite membrane were used to adsorb AuNPs-TiO(2) for immobilizing human chorionic gonadotrophin antibody (anti-hCG) because of its large surface area and satisfactory biocompatibility. At last, BSA was employed to block possible remaining active sites. Under optimized conditions, the immunosensor displayed high sensitivity, good reproducibility, and a low detection limit of 0.08mIU/mL at 3 times the background noise. The ease of non-manual technique and the promising feature of biocomposite could serve as a versatile platform for constructing other biosensors.     

重氮树脂与牛血清白蛋白共价结合自组装膜及其表面细胞培养

细胞支架作为组织工程的组成部分为细胞生长提供了最佳微环境 ,并对细胞生长与功能进行控制 .由于细胞对支架表面的生物识别是细胞附着、生长和增殖的基本前提 ,所以对材料表面的功能化是一个重要的课题 [1,2 ] . Shoichet等 [3 ] 通过化学反应或等离子体处理的方法 ,将蛋白质引入到材料表面而使其功能化 .基片在两种带有相反电荷的聚电解质溶液中交替吸附 ,其表面形成致密有序的超薄自组装膜 ,这种层 -层自组装技术不仅制备方法简单 ,无需特殊的设备 ,而且对膜组成和厚度能随意调控 ,以水为介质 ,对环境友好 [4～ 6] ,无疑是一项重要的表…     

基于N,O-双异丁烯酰乙醇胺为交联功能单体的苯磺隆分子印迹聚合物膜的制备及其性能研究

以苯磺隆为模板分子, N,O-双异丁烯酰乙醇胺为交联功能单体, 在尼龙-6膜上通过紫外光照引发合成了分子印迹聚合物膜, 并用扫描电镜对其表面形态进行了表征. 用紫外分光光谱法研究了模板分子与交联功能单体之间的相互作用. 印迹因子的测定和底物竞争渗透实验结果表明, 分子印迹聚合物膜对模板分子苯磺隆具有较高的选择性, 而非分子印迹聚合物膜没有选择性.