Functionalized self-assembled monolayers on ultraflat gold as platforms for single molecule force spectroscopy and imaging.
Functionalized self-assembled monolayers on ultraflat gold as platforms for single molecule force spectroscopy and imaging.
复制标题
超扁平金上的功能化自组装单层作为单分子力谱和成像的平台。
DOI：
10.1021/la060320h
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Wang,Kuan
中科院分区：
文献类型：
--
作者：
Yadavalli,VamsiK;Forbes,JeffreyG;Wang,Kuan
Single molecule force spectroscopy is a valuable tool for studying unfolding and nanomechanical properties of proteins. The common practice is to stretch proteins from a surface that was dosed to give a reasonable hit rate and to analyze the curves that exhibit the expected characteristics of a single polymer. Whether the surface-bound proteins are indeed single and isolated remains unclear, and the undesirable protein/surface interactions that obscure informative features of the force curves are implicitly assumed to be absent. In this study, mixed self-assembled monolayers (SAMs) consisting ofN-hydroxysuccinimide (NHS) and oligoethylene glycol (OEG) terminated thiols on an ultraflat gold surface were used to covalently immobilize proteins via lysine residues. By the optimization of attachment sites via lysine−NHS linkages amidst a protein-resistant layer of the OEG SAM, it was possible to isolatesingleproteins for study in a controlled fashion. The single protein distribution on the surface is clearly demonstrated by atomic force microscopy (AFM) imaging. The OEG also significantly reduces nonspecific tip−surface interactions between the cantilever and surface. Stretching covalently attached single proteins produces high-quality and reproducible force−extension curves. This experimental strategy is an attractive platform with which to study protein structure, interactions, and nanomechanical properties of single proteins.
