Edvardsson Malin, Svedhem Sofia, Wang Guoliang, Richter Ralf, Rodahl Michael, Kasemo Bengt
Department of Applied Physics, Chalmers University of Technology, SE-41296 Goteborg, Sweden.
Anal Chem. 2009 Jan 1;81(1):349-61. doi: 10.1021/ac801523w.
A novel setup was recently developed, combining quartz crystal microbalance with dissipation monitoring (QCM-D) and optical reflectometry for measurements on one and the same surface of, for example, biomolecular adlayers and interactions ( Rev. Sci. Instr. 2008 , 79 075107 ). This combination was chosen on the basis of prior experience of using QCM-D and optical techniques in separate instruments, which showed both the advantage of employing multiple techniques and the disadvantage of not working with the same surface and (flow) cell. The new instrument provides, for example, information about associated water and structural changes of the adlayers that would often pass unnoticed or be hard to interpret or quantify, using either technique alone. The triple response instrument (QCM-D frequency and dissipation and reflectometry) is here applied to four model systems: (A) formation of supported lipid bilayers (SLBs), (B) lipid exchange between a SLB and transiently adsorbed vesicles, (C) binding of a hydrated peptide on a functionalized SLB, and (D) streptavidin coupling to a biotinylated SLB, followed by attachment of biotinylated vesicles. The results demonstrate three major advantages of the combination instrument: (i) much faster data collection because the experiments are done on one surface for all signals, (ii) a common time axis and the same relative importance of surface kinetics and mass transport because the same liquid sample and the same transport conditions apply, and (iii) new features are discovered about the studied system that would be difficult to unravel in separate instruments.
最近开发了一种新颖的装置，它将石英晶体微天平与耗散监测（QCM-D）以及光学反射测量法相结合，用于在例如生物分子吸附层及其相互作用的同一表面上进行测量（《科学仪器评论》，2008年，79卷，075107期）。这种组合是基于之前在单独仪器中使用QCM-D和光学技术的经验而选择的，这些经验既显示了采用多种技术的优势，也显示了不能在同一表面和（流动）池上工作的劣势。新仪器例如能够提供有关吸附层相关水和结构变化的信息，而仅使用任何一种技术时，这些信息通常会被忽略或难以解释和量化。这里将三响应仪器（QCM-D频率、耗散和反射测量）应用于四个模型系统：（A）支撑脂质双层（SLB）的形成，（B）SLB与瞬时吸附囊泡之间的脂质交换，（C）水合肽在功能化SLB上的结合，以及（D）链霉亲和素与生物素化SLB的偶联，随后连接生物素化囊泡。结果证明了组合仪器的三个主要优点：（i）数据收集速度快得多，因为所有信号的实验都在一个表面上进行；（ii）具有共同的时间轴，并且表面动力学和质量传输具有相同的相对重要性，因为使用的是相同的液体样品和相同的传输条件；（iii）发现了有关所研究系统的新特征，而这些特征在单独的仪器中很难揭示。
