Interfacial tension of the lipid membrane formed from phosphatidylcholine-decanoic acid and phosphatidylcholine-decylamine systems.

Interfacial tension has been determined for phosphatidylcholine (PC)-decanoic acid (DA) and PC-decylamine (DE) membranes. PC (lecithin), DA and DE were used in the experiments; the interfacial tension values of the pure components are 1.62×10(-3), -2.38×10(-2) and -3.88×10(-2) N/m (hypothetical values for DA and DE), respectively. The 1:1 complexes were formed during formation of PC-DA and PC-DE membranes. The following parameters describing the complexes were determined: the surface concentrations of the lipid membranes formed from these complexes, [Formula: see text]; the interfacial tensions of such membranes, γ3; and the stability constants of these complexes, K.