Wilson Kerry A, Finch Craig A, Anderson Phillip, Vollmer Frank, Hickman James J
Nanoscience Technology Center, University of Central Florida, 12424 Research Parkway, Orlando, FL 32826, USA.
The Wyss & Rowland Institutes, Harvard University, 100 Edwin H. Land Blvd, Cambridge, MA 02142, USA.
Biomaterials. 2015 Jan;38:86-96. doi: 10.1016/j.biomaterials.2014.10.002. Epub 2014 Nov 1.
Understanding protein adsorption and resultant conformation changes on modified and unmodified silicon dioxide surfaces is a subject of keen interest in biosensors, microfluidic systems and for medical diagnostics. However, it has been proven difficult to investigate the kinetics of the adsorption process on these surfaces as well as understand the topic of the denaturation of proteins and its effect on enzyme activity. A highly sensitive optical whispering gallery mode (WGM) resonator was used to study a catalytic enzyme's adsorption processes on different silane modified glass substrates (plain glass control, DETA, 13 F, and SiPEG). The WGM sensor was able to obtain high resolution kinetic data of glucose oxidase (GO) adsorption with sensitivity of adsorption better than that possible with SPR. The kinetic data, in combination with a functional assay of the enzyme activity, was used to test hypotheses on adsorption mechanisms. By fitting numerical models to the WGM sensograms for protein adsorption, and by confirming numerical predictions of enzyme activity in a separate assay, we were able to identify mechanisms for GO adsorption on different alkylsilanes and infer information about the adsorption of protein on nanostructured surfaces.
了解蛋白质在改性和未改性二氧化硅表面的吸附以及由此产生的构象变化，是生物传感器、微流控系统和医学诊断领域备受关注的课题。然而，事实证明，研究这些表面上吸附过程的动力学以及理解蛋白质变性的主题及其对酶活性的影响是很困难的。一种高灵敏度的光学回音壁模式（WGM）谐振器被用于研究催化酶在不同硅烷改性玻璃基板（普通玻璃对照、DETA、13F和SiPEG）上的吸附过程。WGM传感器能够获得葡萄糖氧化酶（GO）吸附的高分辨率动力学数据，其吸附灵敏度优于SPR所能达到的灵敏度。动力学数据与酶活性的功能测定相结合，用于检验关于吸附机制的假设。通过将数值模型拟合到蛋白质吸附的WGM传感图，并通过在单独的测定中确认酶活性的数值预测，我们能够确定GO在不同烷基硅烷上的吸附机制，并推断有关蛋白质在纳米结构表面吸附的信息。
