Effect of a polymer cushion on the electrical properties and stability of surface-supported lipid bilayers.
A robust biomimetic cell membrane platform is critical for mechanistic studies of membrane protein channels. While polymer cushions are believed to facilitate the incorporation of membrane proteins in such a platform, a systematic characterization and optimization of such cushions is rarely performed. Here, we examine the influence of a polymer cushion on the electrical properties of supported 1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhPC) bilayers produced via a Langmuir-Blodgett deposition/vesicle fusion assembly process on single-crystal silicon. We show that the resistance of DPhPC bilayers is maximized at the calculated crossover concentration of the polymer (5.9 mol % PEG-lipids). Additionally, these bilayers are sufficiently stable to allow impedance analyses to be performed for nearly 3 weeks. These studies reveal the optimal PEG concentration that yields electrically robust bilayers and demonstrate the utility of the platform for future studies of membrane protein channels and membrane active peptides.
Lin
Janice
J
Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Szymanski
John
J
Searson
Peter C
PC
Hristova
Kalina
K
D025802:Electric Capacitance; D017097:Electric Impedance; D004560:Electricity; D004563:Electrochemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D009038:Motion; D011092:Polyethylene Glycols / Q000737:chemistry*; D011312:Pressure; D013499:Surface Properties
D008051:Lipid Bilayers; D011092:Polyethylene Glycols