The kinetics of surface film formation from Intralipid TM 20% spread at the air-water interface were studied by recording the variations with time of the surface pressure and surface potential. A simple kinetic scheme describing the interfacial destabilization of both emulsion and liposomes particles was developed. The rate constants of the surface transformation of both emulsion and liposomes particles into a mixed triolein-egg phosphatidylcholine (PC) monolayer were determined and compared with the rate constant of the surface transformation of liposomes. The higher rate constant of spreading observed with Intralipid TM was attributed to the higher spreading capacity of the core of the emulsion particles. The rate constant of destabilization of the PC monolayer covering the emulsion particles was nearly twice as high as that of the PC bilayer of liposomes.
It was observed that the surface transformation of Intralipid TM emulsions were accelerated by enzymatic hydrolysis when human gastric lipase and human pancreatic lipase were introduced. It was further confirmed that preincubating the Intralipid TM with HGL and HPL consecutively accelerated the Intralipid destabilization.