New Poly(amino acid methacrylate) Brush Supports the Formation of Well-Defined Lipid Membranes

• Published in: Langmuir Vol. 31; no. 12; pp. 3668 - 3677
• Main Authors: Blakeston, Anita C, Alswieleh, Abdullah M, Heath, George R, Roth, Johannes S, Bao, Peng, Cheng, Nan, Armes, Steven P, Leggett, Graham J, Bushby, Richard J, Evans, Stephen D
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 31.03.2015
• Subjects: Cell Membrane - chemistry; Cysteine - analogs & derivatives; Cysteine - chemistry; Lipid Bilayers - chemistry; Models, Molecular; Molecular Conformation; Phosphorylcholine - analogs & derivatives; Phosphorylcholine - chemistry; Polymerization; Polymers - chemistry; Polymethacrylic Acids - chemistry; Surface Properties
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la504163s

A novel poly­(amino acid methacrylate) brush comprising zwitterionic cysteine groups (PCysMA) was utilized as a support for lipid bilayers. The polymer brush provides a 12-nm-thick cushion between the underlying hard support and the aqueous phase. At neutral pH, the zeta potential of the PCysMA brush was ∼−10 mV. Cationic vesicles containing >25% DOTAP were found to form a homogeneous lipid bilayer, as determined by a combination of surface analytical techniques. The lipid mobility as measured by FRAP (fluorescence recovery after photobleaching) gave diffusion coefficients of ∼1.5 μm2 s–1, which are comparable to those observed for lipid bilayers on glass substrates.