Sequence-dependent force response during peeling of single-stranded DNA from graphite

作     者：Suresh Manohar Anand Jagota 

作者机构：Department of Chemical Engineering Lehigh University Bethlehem Pennsylvania 18015 USA Bioengineering Program Lehigh University Bethlehem Pennsylvania 18015 USA 

出 版 物：《Physical Review E》 (物理学评论E辑：统计、非线性和软体物理学)

年 卷 期：2010年第81卷第2期

页      面：021805-021805页

核心收录：

学科分类：07[理学] 070203[理学-原子与分子物理] 0702[理学-物理学] 

基　　金：National Science Foundation [CMS-0609050] 

主　　题：Free energy 

摘      要：We have analyzed the statistical thermodynamics of peeling single-stranded DNA (ssDNA) from the surface of graphite. Using recently measured parameters, we represent ssDNA as a polymer chain strongly adsorbed to a frictionless substrate using the freely jointed chain, wormlike chain, and rotational isomeric state models. All three models predict steady peeling force under force control, in agreement with single-molecule experiments. We predict that, for finite-length chains, the force response has measurable spikes under displacement control. These force spikes carry information about the underlying sequence of ssDNA, which might thus be measurable with a sufficiently stiff loading system. For the freely jointed chain model, under force control, we have obtained several exact closed-form results and provide relations between the measured peel force and the underlying adhesion free energy.