Formation, Stability, and Mobility of One-Dimensional Lipid Bilayers on Polysilicon Nanowires

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• 作者：Shih-Chieh J. Huang ; Alexander B. Artyukhin ; Julio A. Martinez ; Donald J. Sirbuly ; Yinmin Wang ; Jiann-Wen Ju ; Pieter Stroeve ; Aleksandr Noy
• 刊名：Nano Letters
• 出版年：2007
• 出版时间：November 2007
• 年：2007
• 卷：7
• 期：11
• 页码：3355 - 3359
• 全文大小：470K
• 年卷期：v.7,no.11(November 2007)
• ISSN：1530-6992

文摘

Curved lipid membranes are ubiquitous in living systems and play an important role in many biological processes. To understand howcurvature and lipid composition affect membrane formation and fluidity, we have assembled and studied mixed 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) supported lipid bilayers on amorphous silicon nanowiresgrown around carbon nanotube cores with controlled wire diameters ranging from 20 to 200 nm. We found that lipid vesicles fused ontonanowire substrates and formed continuous bilayers for all DOPC-DOPE mixtures tested (with the DOPE content of up to 30%). Our measurementsdemonstrate that nanowire-supported bilayers are mobile, exhibit fast recovery after photobleaching, and have a low concentration of defects.Lipid diffusion coefficients in these high-curvature tubular membranes are comparable to the values reported for flat supported bilayers andincrease slightly with decreasing nanowire diameter. A free space diffusion model adequately describes the effect of bilayer curvature on thelipid mobility for nanowire substrates with diameters greater than 50 nm, but shows significant deviations from the experimental values forsmaller diameter nanowires.