Biswas Kabir H, Jackman Joshua A, Park Jae Hyeon, Groves Jay T, Cho Nam-Joon
School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, 639798 Singapore.
Department of Chemistry, University of California, Berkeley , Berkeley, California 94720, United States.
Langmuir. 2018 Jan 30;34(4):1775-1782. doi: 10.1021/acs.langmuir.7b03799. Epub 2018 Jan 11.
The pathway of vesicle adsorption onto a solid support depends on the material composition of the underlying support, and there is significant interest in developing material-independent strategies to modulate the spectrum of vesicle-substrate interactions on a particular surface. Herein, using the quartz crystal microbalance-dissipation (QCM-D) technique, we systematically investigated how solution pH and membrane surface charge affect vesicle adsorption onto a silicon dioxide surface. While vesicle adsorption and spontaneous rupture to form complete supported lipid bilayer (SLBs) occurred in acidic conditions, it was discovered that a wide range of adsorption pathways occurred in alkaline conditions, including (i) vesicle adsorption and spontaneous rupture to form complete SLBs, (ii) vesicle adsorption and spontaneous rupture to form incomplete SLBs, (iii) irreversible adsorption of intact vesicles, (iv) reversible adsorption of intact vesicles, and (v) negligible adsorption. In general, SLB formation became more favorable with increasingly positive membrane surface charge although there were certain conditions at which attractive electrostatic forces were insufficient to promote vesicle rupture. To rationalize these findings, we discuss how solution pH and membrane surface charge affect interfacial forces involved in vesicle-substrate interactions. Taken together, our findings present a comprehensive picture of how interfacial forces dictate the pathway of phospholipid vesicle adsorption onto silicon dioxide surfaces and offer a broadly applicable framework to characterize the interactions between phospholipid vesicles and inorganic material surfaces.
囊泡吸附到固体载体上的途径取决于底层载体的材料组成，因此人们对开发与材料无关的策略以调节特定表面上囊泡与底物相互作用的范围有着浓厚兴趣。在此，我们使用石英晶体微天平耗散（QCM-D）技术，系统地研究了溶液pH值和膜表面电荷如何影响囊泡在二氧化硅表面的吸附。虽然囊泡吸附和自发破裂形成完整的支撑脂质双层（SLB）在酸性条件下发生，但发现在碱性条件下会出现多种吸附途径，包括：（i）囊泡吸附和自发破裂形成完整的SLB；（ii）囊泡吸附和自发破裂形成不完整的SLB；（iii）完整囊泡的不可逆吸附；（iv）完整囊泡的可逆吸附；以及（v）可忽略不计的吸附。一般来说，尽管在某些条件下有吸引力的静电力不足以促进囊泡破裂，但随着膜表面电荷越来越正，SLB的形成变得更有利。为了合理解释这些发现，我们讨论了溶液pH值和膜表面电荷如何影响囊泡与底物相互作用中涉及的界面力。综上所述，我们的研究结果全面展示了界面力如何决定磷脂囊泡在二氧化硅表面的吸附途径，并提供了一个广泛适用的框架来表征磷脂囊泡与无机材料表面之间的相互作用。
