Wood Mary H, Milan David C, Nichols Richard J, Casford Michael T L, Horswell Sarah L
School of Chemistry, University of Birmingham Birmingham B15 2TT UK
Department of Chemistry, University of Liverpool Liverpool L69 7ZD UK.
RSC Adv. 2021 Jun 2;11(32):19768-19778. doi: 10.1039/d1ra01920a. eCollection 2021 May 27.
The efficacy of a number of different methods for depositing a dimyristoylphosphatidylcholine (DMPC) lipid bilayer or DMPC-cholesterol (3 : 1) mixed bilayer onto a silicon substrate has been investigated in a quantitative manner using atomic force microscopy (AFM) image analysis to extract surface coverage. Complementary AFM-IR measurements were used to confirm the presence of the lipids. For the Langmuir-Blodgett/Schaefer deposition method at temperatures below the chain-melting transition temperature ( ), a large number of bilayer defects resulted when DMPC was deposited from a water subphase. Addition of calcium ions to the trough led to smaller, more frequent defects, whereas addition of cholesterol to the lipid mixture led to a vast improvement in bilayer coverage. Poor coverage was achieved for deposition at temperatures above . Formation of the deposited bilayer from vesicle fusion proved a more reliable method for all systems, with formation of near-complete bilayers within 60 seconds at temperatures above , although this method led to a higher probability of multilayer formation and rougher bilayer surfaces.
已采用原子力显微镜（AFM）图像分析定量研究了多种不同方法将二肉豆蔻酰磷脂酰胆碱（DMPC）脂质双层或DMPC - 胆固醇（3∶1）混合双层沉积到硅基底上的效果，以提取表面覆盖率。使用互补的AFM - IR测量来确认脂质的存在。对于在低于链熔化转变温度（ ）的温度下的朗缪尔 - 布洛杰特/谢弗沉积方法，当从水亚相沉积DMPC时会产生大量双层缺陷。向槽中添加钙离子会导致更小、更频繁的缺陷，而向脂质混合物中添加胆固醇会使双层覆盖率有很大提高。在高于 的温度下沉积时覆盖率较差。对于所有系统而言，通过囊泡融合形成沉积双层是一种更可靠的方法，在高于 的温度下60秒内可形成近乎完整的双层，尽管这种方法导致形成多层的可能性更高且双层表面更粗糙。
