Liang Hsin-Hui, Chen Hsuan-Yi
Department of Physics, National Central University, Jhongli, Taiwan.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Jun;83(6 Pt 1):061914. doi: 10.1103/PhysRevE.83.061914. Epub 2011 Jun 16.
A cluster of N ligand-receptor pairs between two parallel surfaces under an applied force F=Γt with a constant loading rate Γ is considered. Our theoretical and numerical studies show that there is a characteristic force f(c) and a characteristic loading rate Γ(c). At Γ<Γ(c), the mean rupture force F(r) of the cluster is close to but lower than Nf(c). In this regime, cluster dissociation can be modeled as a one-dimensional barrier crossing process and F(r) scales like Nf(c)-F(r)~N(1/3)ln(Γ(c)/Γ). At Γ=Γ(c), the cluster dissociation occurs at F(r)=Nf(c). At Γ>Γ(c), F(r) for clusters with large N is well predicted by the rate equation because the fluctuations of the number of closed bonds are unimportant. Our study shows that f(c) and Γ(c) are important emergent properties for understanding the mechanical response of adhesion clusters.
考虑在恒定加载速率Γ下，外力F = Γt作用于两个平行表面之间的一组N个配体 - 受体对。我们的理论和数值研究表明，存在一个特征力f(c)和一个特征加载速率Γ(c)。当Γ < Γ(c)时，该组的平均断裂力F(r)接近但低于Nf(c)。在这种情况下，组的解离可以建模为一维势垒穿越过程，并且F(r)的标度关系为Nf(c) - F(r) ~ N(1/3)ln(Γ(c)/Γ)。当Γ = Γ(c)时，组的解离发生在F(r) = Nf(c)处。当Γ > Γ(c)时，对于大N的组，F(r)可以由速率方程很好地预测，因为封闭键数量的波动并不重要。我们的研究表明，f(c)和Γ(c)是理解粘附簇机械响应的重要涌现性质。
