One-step synthesis of a fluorescent phospholipid-hydrogel conjugate for driving self-assembly of supported lipid membranes

We have synthesized a phospholipid-hydrogel conjugate that appears to drive the self-assembly of lipid membranes. A one-step radical polymerization synthesis of the conjugate was devised using lipid anchors that contain a fluorescent marker and a reactive vinyl group. The anchors preferentially located at oil-water interfaces during hydrogel formation and through their vinyl groups became covalently attached at the hydrogel surface. X-ray photoelectron spectroscopy and laser scanning confocal microscopy confirmed surface localization of the anchors. Upon mixing the conjugates with liposomes, lipid membranes readily self-assembled around the lipid-modified hydrogel surfaces. Control experiments with anchorless hydrogels indicate that anchors influenced the surface density and morphology of the lipid membranes. The one-step synthesis allows for simple control of surface anchor density and thus potential control of lipid membrane properties; the fluorescent markers facilitate anchor quantitation and further membrane interaction studies. Potential applications include high throughput drug screening, diagnostics, cell models, and drug delivery.