标题： 聚合物跨膜分析的力光谱分析 显示英文标题

标题： Force spectroscopy analysis in polymer translocation

摘要： 本文报告了通过一个延伸的孔洞从膜的一侧转移到另一侧的聚合物的力谱分析，该过程由一个以恒定速度移动并克服膜壁反应产生的阻尼和势垒的悬臂进行拉伸。 该聚合物被建模为具有排斥体积和弯曲贡献的珠-弹簧链，并在由固定温度下的朗之万动力学描述的随机三维环境中运动。 在不同速度下记录的力轨迹揭示了两种未被探索的指数区域：当链的第一部分进入孔洞时，力增加，然后当第一个单体到达反面区域时，力减少。 力值的谱分析允许估算自由能势垒以及促进转移的极限力。 还独立计算了保持聚合物固定的停顿力，其值证实了力谱分析的结果。 显示英文摘要

摘要： This paper reports the force spectroscopy analysis of a polymer that translocates from one side of a membrane to the other side through an extended pore, pulled by a cantilever that moves with constant velocity against the damping and the potential barrier generated by the reaction of the membrane walls. The polymer is modeled as a beads-springs chain with both excluded volume and bending contributions, and moves in a stochastic three dimensional environment described by a Langevin dynamics at fixed temperature. The force trajectories recorded at different velocities reveal two unexplored exponential regimes: the force increases when the first part of the chain enters the pore, and then decreases when the first monomer reaches the trans region. The spectroscopy analysis of the force values permit the estimation of the free energy barrier as well as the limit force to permit the translocation. The stall force to maintain the polymer fixed has been also calculated independently, and its value confirms the force spectroscopy outcomes.