Alexeev Alexander, Uspal William E, Balazs Anna C
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
ACS Nano. 2008 Jun;2(6):1117-22. doi: 10.1021/nn8000998.
We use a coarse-grained numerical simulation to design a synthetic membrane with stable pores that can be controllably opened and closed. Specifically, we use dissipative particle dynamics to probe the interactions between lipid bilayer membranes and nanoparticles. The particles are nanoscopic Janus beads that comprise both hydrophobic and hydrophilic portions. We demonstrate that when the membrane rips and forms a hole due to an external stress, these nanoparticles diffuse to the edge of the hole and form a stable pore, which persists after the stress is released. Once the particle-lined pore is formed, a small increase in membrane tension readily reopens the pore, allowing transport through the membrane. Besides the application of an external force, the membrane tension can be altered by varying, for example, temperature or pH. Thus, the findings provide guidelines for designing nanoparticle-bilayer assemblies for targeted delivery, where the pores open and the cargo is released only when the local environmental conditions reach a critical value.
我们使用粗粒度数值模拟来设计一种具有稳定孔隙的合成膜，该孔隙能够可控地打开和关闭。具体而言，我们使用耗散粒子动力学来探究脂质双层膜与纳米颗粒之间的相互作用。这些粒子是包含疏水和亲水部分的纳米级Janus珠。我们证明，当膜由于外部应力而撕裂并形成一个孔时，这些纳米颗粒扩散到孔的边缘并形成一个稳定的孔隙，该孔隙在应力释放后仍然存在。一旦形成了由粒子排列的孔隙，膜张力的小幅增加很容易重新打开孔隙，从而允许物质通过膜进行传输。除了施加外力之外，膜张力还可以通过改变例如温度或pH值来改变。因此，这些发现为设计用于靶向递送的纳米颗粒 - 双层组件提供了指导原则，其中孔隙仅在局部环境条件达到临界值时打开并释放货物。
