石英晶体微天平技术研究咪唑类离子液体与气体分子的相互作用

基于石英晶体微天平(Quartz Crystal Microbalance, QCM)技术, 建立了一种测定气体在离子液体(ILs)中基本热力学参数的方法. 测定了5种可挥发有机物(VOCs)在6种咪唑类离子液体中的亨利常数, 并对可能的作用机理进行了探讨. 结果表明, QCM技术可以作为研究离子液体溶解性和作用规律的有效方法.     

石英晶体微天平（QCM）及其在电化学研究中的应用

本文文献综述近年来发展起来的石英晶体微天平(QCM)技术的理论、实验方法和它在电化学研究中应用的概况。     

杂交及切断过程的QCM实时检测研究(英文)

采用自组装技术,将 5′端标记有巯基的 20-merODN(oligo 1)以金 硫键形式牢固结合在 7. 995MHz的AT-切石英晶体的镀金表面,然后由石英晶体微天平实时检测了与碱基序列互补的 10 merODN (oligo 2)和 8 merODN(oligo 3)的杂交,同时还研究了稀土金属铈离子在温和条件下对DNA的水解切断作用.结果表明:应用QCM方法可能实时检测DNA的固定和杂交,Ce(IV)能随机切断单链DNA;但不能切断杂交形成的双链DNA,因此可利用杂交保护的方法对单链DNA实行定位切断.     

石英晶体微天平在聚合物薄膜研究中的应用与展望

石英晶体微天平仪(QCM)具有高度的灵敏性,能够对石英晶片表面微痕量物质的变化产生响应,在分析科学研究中广泛应用.本文阐述了QCM的基本工作原理和应用基础方程,并在此基础上综述了近年来QCM在聚合物薄膜研究中的应用及研究进展,包括QCM对聚合物薄膜的厚度和力学性能的测量、QCM研究聚合物分子链在石英晶片表面的吸附过程和链构象变化、表面引发生长聚合物刷的动力学过程、基于功能聚合物薄膜和QCM的生物与化学传感器等,同时对QCM在聚合物薄膜研究领域的进一步深入应用进行了展望.     

石英晶体微天平用于免疫球蛋白M免疫反应的动力学研究

在镀银电极的压电石英晶体表面涂覆甲基丙烯酸甲酯－甲基丙烯酸羟乙酯共聚物涂层，经ＣＮＢｒ活化后固定抗体，用石英晶体微天平技术监测ＩｇＭ抗原在压电石英晶体上的吸附与解吸过程，研究了免疫反应体系ＩｇＭ－抗人ＩｇＭ的反应动力学．结果表明：ＩｇＭ在压电石英晶体上的键合行为很好地符合Ｌａｎｇｍｕｉｒ吸附方程，免疫反应的结合常数Ｋａｓｓ为７．１０×１０￣７（ｍｏｌ／Ｌ）￣（－１）．在抗原过量情况下为一级反应。计算了ＩｇＭ免疫反应的活化能Ｅａ和不同温度下的反应速率常数ｋｆ．     

电化学石英晶体微天平研究普鲁士蓝修饰电极

石英晶体徽天平(Quartz Crystal Microbalance,简称QCM)是一种非常灵敏的质量传感器,其检测能力可达ng级。QCM在化学中的早期应用是检测大气中的徽量成分,目前仍较活跃。由于石英压电晶体浸入溶液后在晶体/溶液界面存在较大的能量损失而不能够稳定振荡,致使QCM的应用较长时间局限于气相。八十年代初石英压电晶体在液相中的振荡终获成功,开辟了QCM应用的一个全新领域。液相中振荡成功后,QCM很快应用于电化学研究。目前已发展成为一种全新的电化学传感器——电化学石英晶体微天平(EQCM),并已用于金属电沉积、电化学腐蚀、电分析等方面的研究。     

萘磺酸盐与β-环糊精衍生物的包结行为

以自组装方式在石英晶体谐振器的金电极表面修饰末端含巯基的β 环糊精衍生物（β CDd）,用石英晶体微天平（QCM）在线监测α 、β 萘磺酸盐与之发生包结反应的过程,探讨了温度、浓度、取代基位置对包结反应稳定常数Kin和速率常数ka的影响.从理论上推导并通过实验验证了Kin和ka所遵从的关系式.结果表明：所形成的包结配合物中β CDd与萘磺酸盐的化学计量均为1:1;包结配位反应过程符合Langmuir吸附模型;取代基在萘环上的位置对Kin和ka有很大影响,说明不同取代位置的萘磺酸盐与β CDd的包结行为存在明显差异.     

基于糖和苯硼酸动态共价键的高效蛋白质表面修饰方法

糖和蛋白质的相互作用参与了很多重要的生命过程.研究糖和蛋白质的相互作用有多种手段,石英晶体微天平(QCM)是其中重要的一种.研究中常需要将蛋白质通过共价键连接在天平芯片的表面.但是,用于检测糖分子的蛋白质多为植物凝集素,它们的分子量大,表面可修饰位点少,通过共价键修饰在芯片表面的效率偏低.本文提出一种基于糖和苯硼酸之间动态共价键的新修饰方法,能够大幅度提高蛋白质在芯片表面的修饰效率.     

乳液聚合中聚苯胺膜形成的动力学研究

以(NH4)2S2O8(APS)为氧化剂,十二烷基苯磺酸(DBSA)同时为乳化剂和掺杂剂,采用乳液聚合方法制备聚苯胺膜(PANIfilm),用石英晶体微天平(QCM)实时监测聚苯胺膜的形成过程,并对其动力学过程进行研究.结果表明,聚苯胺成膜反应对APS是0.5级,对苯胺是1级,聚苯胺膜增长速率随温度的升高而增加,而聚苯胺膜的最终沉积量却减小,表观活化能Ea=41.15kJ/mol,与均相溶液聚合成膜法的结果相近;随着DBSA浓度的增加,聚苯胺膜增长速率减小,而最终的沉积量增大.     

Cellulose nanofibrils—adsorption with poly(amideamine) epichlorohydrin studied by QCM-D and application as a paper strength additive

In this paper cellulose nanofibrils were used together with a cationic polylelectrolyte, poly(amideamine) epichlorohydrin (PAE), to enhance the wet and the dry strength of paper. The adsorption of nanofibrils and PAE on cellulose model surfaces was studied using quartz crystal microbalance with dissipation (QCM-D) and atomic force microscopy (AFM). The differences in fibril and polyelectrolyte adding strategies onto cellulose fibres were studied by comparing layer-structures and nano-aggregates formed by the nanofibrils and PAE. The results showed that when PAE was first adsorbed on the model fibre surface a uniform and viscous layer of nanofibrils could be adsorbed. When PAE and nanofibrils were adsorbed as cationic aggregates a non-uniform and more rigid layer was adsorbed. Paper sheets were prepared using both the bi-layer and nano-aggregate adding strategy of the nanofibrils and PAE. When PAE and nanofibrils were adsorbed on pulp fibres as a bi-layer system significant increase in both wet and dry tensile strength of paper could be achieved even at low added amounts of PAE. When the substances were added as nano-aggregates the improvements in paper strength properties were not as significant. Bulk and surface nitrogen content analyses of the paper samples showed that the adding strategy does not affect the total adsorbed amount of PAE but it has a strong effect on distribution of substances in the paper matrix which has a crucial effect on paper wet and dry strength development.     

Interaction of Plasma Proteins with Tri‐quaternary Ammonium Salt Cationic Surfactant Studied by QCM‐D

A tri‐quaternary ammonium salt cationic surfactant was synthesized. Its structure was confirmed by using Fourier‐transform infrared spectroscopy, ¹H nuclear magnetic resonance spectroscopy, and X‐ray photoelectron spectroscopy analyses. Three model surfaces, including Au‐CH₃, Au‐OH and Au‐COOH, were fabricated. Adsorptions of surfactant on the three model surfaces and subsequent plasma proteins adsorption were investigated by quartz crystal microbalance with dissipation (QCM‐D). The mass of surfactant on the Au‐COOH surface was the largest, followed by that on the Au‐CH₃ surface, and that on the Au‐OH surface. These results suggested that the main driving force of surfactant immobilization was electrostatic interaction followed by hydrophobic interaction. Based on the results obtained, we concluded that the protein mass adsorbed on Au‐CH₃‐ S , Au‐OH‐ S , and Au‐COOH‐ S surfaces depended on the protein size and orientation. The mass and thickness of S on the Au‐COOH surface is the largest and the protein adsorption capacity of Au‐COOH‐ S surface is inferior to that of Au‐CH₃‐ S . The Au‐COOH‐ S surface could inhibit lysozyme adsorption, maintain the adsorption balance of bovine serum albumin, and induce fibrinogen‐binding protein adsorption.     

Water Content of Hydrated Polymer Brushes Measured by an In Situ Combination of a Quartz Crystal Microbalance with Dissipation Monitoring and Spectroscopic Ellipsometry

Poly(methacryloyloxy ethyltrimethylammonium chloride) (PMETAC), poly(sulfopropylmethacrylate potassium salt), or poly(N‐isopropyl acrylamide) (PNIPAM) brushes are synthesized by means of the atom transfer radical polymerization technique from gold surfaces coated with a monolayer of the initiator ω‐mercaptoundecyl bromo isobutyrate. The brush growth is followed in situ and in real time by the combination of quartz crystal microbalance with dissipation technique (QCM‐D) and spectroscopic ellipsometry in a single device. The combination of QCM‐D and ellipsometry allows for the simultaneous determination of both the acoustic mass, m_acous, comprising the mass of the polymer and the solvent, and the optical mass, m_opt, which corresponds to the polymer mass alone. Brush hydration is calculated from the difference between the values obtained for m_acous and m_opt for each polymer synthesized. Brush hydration is then used to quantify the percentage of water released in the brush during collapse; a 30–40% release of water for PMETAC and PSPM brushes in 1 M NaCl and 80% for PNIPAM brushes when the temperature is increased to values above the lower critical solution temperature is observed.     

电化学石英晶体微天平研究界面电场对DNA杂交的影响

采用电化学石英晶体微天平, 现场监测不同界面电场下完全匹配的靶标DNA和不完全匹配的靶标DNA分别与寡聚核苷酸探针分子杂交的过程. 结果表明, 电极表面荷正电时DNA表观杂交效率比电极表面荷负电时高, 但假阳性比较显著; 而电极表面荷负电时能有效地抑制错配杂交. 探讨了引入界面电场后探针分子取向和微观作用力对DNA杂交的影响.     

耗散型石英晶体微天平在生物医用高分子材料中的应用

石英晶体微天平(QCM)是一种基于石英晶体压电效应的分析检测技术,可实时在线提供石英晶体表面吸附层质量、厚度、粘弹性等信息,由此获得表面分子相互作用关系。 耗散型石英晶体微天平(QCM-D)因其独特的对粘弹性的解析,使其在高分子材料中的应用迅速发展,尤其是生物医用高分子材料领域,已用来评价生物医用高分子材料的表界面相互作用,力学和生物相容性等。 本文简单介绍了耗散型石英晶体微天平的基本原理及理论模型,重点综述了近几年QCM-D在高分子链构象、蛋白质吸附、生物大分子相互作用、药物释放以及水凝胶中的应用,并且展望了QCM-D的未来发展趋势。     

A practical guide to quartz crystal microbalance with dissipation monitoring of thin polymer films

Quartz crystal microbalance with dissipation (QCM-D) monitoring is a powerful tool used to sensitively examine the real-time responses of polymer films to external responses. For example, the technique is commonly used to monitor film growth, material adsorption, thin film swelling, and ion exchange. With its rapidly expanding use, this review is intended to introduce new users to the basic principles of QCM-D, along with practical challenges and remedies specific to polymer thin films. For both new and experienced users, specific case studies are highlighted including layer-by-layer assembly, electrochemical QCM-D, swelling, sensing, and biological application. Last, the review recommends future directions for research and areas of growth.     

石英晶体微天平技术研究纳米TiO_2表面Cu(Ⅱ)吸附与光化学还原过程

环境中排放的重金属离子Cu!对水生和陆生生物有强的毒害性。饮用水中Cu!的浓度高于1.0mg·L-1时,将会导致人畜得血色沉着病和胃肠粘膜病[1]。Cu!无法进行生物降解,除去废水中Cu!的常见方法有离子交换、置换、化学沉淀等[2],然而这些方法需要消耗大量的化学试剂,成本高。近来,研     

Nanoscale evaluation of lubricity on well-defined polymer brush surfaces using QCM-D and AFM

For preparing a “highly lubricated biointerface”, which has both excellent lubricity and biocompatibility, we investigated the factors responsible for resistance to friction during polymer grafting. We prepared poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), poly(2-hydroxyethyl methacrylate) (PHEMA), and poly(methyl methacrylate) (PMMA) brush layers with high graft density and well-controlled thickness using atom transfer radical polymerization (ATRP). We measured the water absorptivity in the polymer brush layers and the viscoelasticity of the polymer-hydrated layers using a quartz crystal microbalance with dissipation monitoring (QCM-D) measurements. The PMPC brush layer had the highest water absorptivity, while the PMPC-hydrated layer had the highest fluidity. The friction properties of the polymer brush layers were determined in air, water, and toluene by atomic force microscopy (AFM). The friction on each polymer brush decreased only when a good solvent was chosen for each polymer. In conclusion, the brush layer possessing high water absorptivity and fluidity in water contributes to reduce friction. PMPC grafting is an effective and promising method for obtaining highly lubricated biointerfaces.     

Voltammetric Detection of Oxidative DNA Damage Based on Interactions between Polymeric Dyes and DNA

Oxidative damage of DNA was assessed with glassy carbon electrode (GCE) coated with electropolymerized Methylene Blue (MB). For this purpose, DNA solution was first mixed with an oxidant (Fenton reagent, H₂O₂ alone and in the presence of Cu(II) ions) and then placed on the polymeric film surface. After washing, the cyclic voltammogram was recorded in buffer solution and the anodic peak potential measured against that before the contact with DNA. Oxidative DNA damage resulted in remarkable decrease of the anodic peak potential which depended on the oxidant nature and incubation period. Specificity of the DNA – MB interactions was confirmed by surface plasmon resonance (SPR) measurements. Similar experiment performed with polymerized Methylene Green (MG) and Neutral Red (NR) showed lower selectivity of the response toward various sources of reactive oxygen species. The protocol of the DNA damage detection was tested on the estimation of antioxidant properties of green tea extract and red table wine.     

石英晶体微天平在手性识别中的应用

石英晶体微天平(QCM)是一类重要的质量型检测器,因具有灵敏度高、分析速度快、检测成本低等优点而具有极好的应用前景,现已广泛应用于环境监测、药物分析、食品质量控制等诸多领域。手性工程的崛起对简单、快速、在线的手性检测技术提出了挑战,QCM手性传感器就是其中一个重要的发展分支。该文简要介绍了QCM的典型实验装置和基本传感原理,详细综述了近年来QCM在手性识别领域的研究进展,包括以环糊精衍生物、分子印迹聚合物、氨基酸衍生物等为手性主体的QCM在手性识别中的应用,并对其今后的发展进行了展望。