| Abstract
| - To investigate protein and cell surface interactions, robust and increasingly complex model surfacesneed to be developed to mimic specific aspects of the cell membrane structure. Polymer-supported lipidmonolayers and bilayers present an opportunity to develop rugged cell mimetic surfaces that may be stablein a wide range of in vivo and in vitro applications and characterization techniques. We have investigatedthe stability of dimyristoylphosphatidylethanolamine (DMPE) monolayers grafted to poly(hydroxyethylmethacrylate) (pHEMA) via 1,1‘-carbonyldiimidazole (CDI) chemistry using X-ray photoelectron spectroscopy(XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and fluorescence microscopy. The resultsillustrate that it is possible to covalently couple the amine-containing lipid headgroup to the carboxyl andhydroxyl groups of the pHEMA and retain a proportion of the lipids at the surface after the samples aresonicated in ethanol. Most importantly, the cross-linking efficiency and retention of the resulting lipidlayer is higher if the lipid is transferred to CDI-activated HEMA by Langmuir−Blodgett deposition ratherthan by adsorption of the lipid directly from solution. Both factors are critical if these monolayers are toform a stable and reproducible model system.
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