School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue 639798 , Singapore.
School of Chemical Engineering , Sungkyunkwan University , Suwon 16419 , Republic of Korea.
Langmuir. 2019 Jun 25;35(25):8436-8444. doi: 10.1021/acs.langmuir.9b00570. Epub 2019 Jun 10.
The adsorption of two-dimensional bicellar disks onto solid supports is an emerging fabrication technique to form supported lipid bilayers (SLBs) that is efficient and requires minimal sample preparation. To date, nearly all relevant studies have focused on zwitterionic lipid compositions and silica-based surfaces, and extending the scope of investigation to other lipid compositions and surfaces would improve our understanding of application possibilities and underpinning formation processes. Herein, using the quartz crystal microbalance-dissipation technique, we systematically investigated the adsorption of charged lipid bicelles onto silicon dioxide, titanium oxide, and aluminum oxide surfaces. Depending on the lipid composition and substrate, we observed different adsorption pathways, including (i) SLB formation via one- or two-step adsorption kinetics, (ii) monotonic adsorption without SLB formation, and (iii) negligible adsorption. On each substrate, SLB formation could be achieved with particular lipid compositions, whereas the trend in adsorption pathways varied according to the substrate and could be controlled by adjusting the bicelle?substrate interaction strength. To rationalize these findings, we discuss how electrostatic and hydration forces affect bicelle?substrate interactions on different oxide surfaces. Collectively, our findings demonstrate the broad utility of lipid bicelles for SLB formation while revealing physicochemical insights into the role of interfacial forces in controlling bicelle adsorption pathways.
二维双分子囊泡吸附到固体支撑物上是一种新兴的制造技术，可用于形成支撑脂质双层（SLB），这种技术效率高，所需的样品制备工作量最小。迄今为止，几乎所有相关研究都集中在两性离子脂质组成和基于硅的表面上，将研究范围扩展到其他脂质组成和表面将提高我们对应用可能性和基础形成过程的理解。在此，我们使用石英晶体微天平耗散技术，系统地研究了带电荷的脂质双分子囊泡在二氧化硅、氧化钛和氧化铝表面上的吸附。根据脂质组成和基底的不同，我们观察到了不同的吸附途径，包括(i) 通过一步或两步吸附动力学形成 SLB，(ii) 没有 SLB 形成的单调吸附，和 (iii) 可忽略的吸附。在每种基底上，都可以用特定的脂质组成来实现 SLB 的形成，而吸附途径的趋势则根据基底而变化，并可以通过调节双分子囊泡-基底相互作用强度来控制。为了合理化这些发现，我们讨论了静电和水合作用力如何影响不同氧化物表面上双分子囊泡-基底相互作用。总的来说，我们的发现证明了脂质双分子囊泡在形成 SLB 方面的广泛适用性，同时揭示了界面力在控制双分子囊泡吸附途径方面的物理化学作用。
