Institut für Physikalische Chemie , Universität Mainz , Duesbergweg 10-14 , 55128 Mainz , Germany.
J Phys Chem B. 2019 Jun 6;123(22):4688-4694. doi: 10.1021/acs.jpcb.9b02676. Epub 2019 May 22.
We present force probe molecular dynamics simulations of dimers of interlocked calixarene nanocapsules and study the impact of structural details and solvent properties on the mechanical unfolding pathways. The system consists of two calixarene "cups" that form a catenane structure via interlocked aliphatic loops of tunable length. The dimer shows reversible rebinding, and the kinetics of the system can be understood in terms of a two-state model for shorter loops (≤14 CH units) and a three-state model for longer loops (≥15 CH units). The various conformational states of the dimer are stabilized by networks of hydrogen bonds, the mechanical susceptibility of which can be altered by changing the polarity and proticity of the solvent. The variation of the loop length and the solvent properties in combination with changes in the pulling protocol allows to tune the reversibility of the conformational transitions.
我们呈现了互锁杯芳烃纳米胶囊二聚体的力探针分子动力学模拟，并研究了结构细节和溶剂性质对机械解折叠途径的影响。该系统由两个杯芳烃“杯子”组成，通过可调节长度的互锁脂肪环形成轮烷结构。二聚体表现出可重复的结合，并且系统的动力学可以根据较短环（≤14 CH 单元）的两态模型和较长环（≥15 CH 单元）的三态模型来理解。二聚体的各种构象状态由氢键网络稳定，通过改变溶剂的极性和质子性，可以改变氢键网络的机械敏感性。环长度和溶剂性质的变化以及拉伸方案的变化允许调节构象转变的可逆性。
