1-palmitoyl-2-oleoylphosphatidylcholine and sodium-sulfate

meso-Octamethyloctafluorocalixpyrrole, a simple tetrapyrrolic macrocycle, has been shown to function as both a chloride/nitrate and a chloride/bicarbonate antiport agent for lipid bilayer transmembrane anion transport. This is the first example of a synthetic macrocyclic pyrrole-based receptor capable of transmembrane bicarbonate transport.

Topics: Anions; Bicarbonates; Calixarenes; Chloride-Bicarbonate Antiporters; Lipid Bilayers; Nitrates; Phosphatidylcholines; Porphyrins; Sodium Chloride; Sulfates

The absorption and spreading behavior of lipid vesicles composed of either palmitoyloleoylphosphatidylcholine (POPC) or Escherichia coli lipid upon contact with a glass surface was examined by fluorescence measurements. Fluorescently labeled lipids were used to determine 1) the amount of lipid adsorbed at the surface, 2) the extent of fusion of the vesicles upon contact with the surface, 3) the ability of the adsorbed lipids to undergo lateral diffusion, and 4) the accessibility of the adsorbed lipids by external water soluble molecules. The results of these measurements indicate that POPC vesicles spread on the surface and form a supported planar bilayer, whereas E. coli lipid vesicles adsorb to the surface and form a supported vesicle layer. Supported planar bilayers were found to be permeable for small molecules, whereas supported vesicles were impermeable and thus represented immobilized, topologically separate compartments.

Topics: Adsorption; Diffusion; Escherichia coli; Lipid Bilayers; Membrane Fusion; Phosphatidylcholines; Phospholipids; Sulfates; Surface Properties