Department of Physics, University of Massachusetts Amherst, USA.
Nanoscale. 2019 Oct 10;11(39):18464-18474. doi: 10.1039/c9nr06570a.
While cells offer numerous inspiring examples in which membrane morphology and function are controlled by interactions with viruses or proteins, we still lack design principles for controlling membrane morphology in synthetic systems. With experiments and simulations, we show that spherical nanoparticles binding to lipid-bilayer membrane vesicles results in a remarkably rich set of collective morphologies that are controllable via the particle binding energy. We separately study cationic and anionic particles, where the adhesion is tuned by addition of oppositely charged lipids to the vesicles. When the binding energy is weak relative to a characteristic membrane-bending energy, vesicles adhere to one another and form a soft solid gel, a novel and useful platform for controlled release. With larger binding energy, a transition from partial to complete wrapping of the nanoparticles causes a remarkable vesicle destruction process culminating in rupture, nanoparticle-membrane tubules, and an apparent inversion of the vesicles. These findings help unify the diverse phenomena observed previously. They also open the door to a new class of vesicle-based, closed-cell gels that are more than 99% water and can encapsulate and release on demand, and show how to drive intentional membrane remodeling for shape-responsive systems.
虽然细胞提供了许多令人鼓舞的例子，说明膜形态和功能可以通过与病毒或蛋白质的相互作用来控制，但我们仍然缺乏控制合成系统中膜形态的设计原则。通过实验和模拟，我们表明，球形纳米粒子与脂质双层膜泡结合会导致一组非常丰富的集体形态，这些形态可以通过粒子结合能来控制。我们分别研究阳离子和阴离子粒子，其中通过向囊泡添加带相反电荷的脂质来调节粘附。当结合能相对于特征膜弯曲能较弱时，囊泡彼此粘附并形成软固态凝胶，这是一种用于控制释放的新颖而有用的平台。随着结合能的增大，纳米粒子的部分到完全包裹的转变会导致囊泡的显著破坏过程，最终导致破裂、纳米粒子-膜小管和囊泡的明显反转。这些发现有助于统一以前观察到的各种现象。它们还为一类新的基于囊泡的封闭细胞凝胶打开了大门，这种凝胶的水含量超过 99%，可以按需封装和释放，并展示了如何为形状响应系统驱动有意的膜重塑。
