Stabilized complex film formed by co-adsorption of β-lactoglobulin and phospholipids at liquid/liquid interface

A complex film has been formed at a drop surface by the co-adsorption of β-lactoglobulin with the l-α-dipalmitoylphosphatidylcholine (DPPC), l-α-dipalmitoylphosphatidyl-ethanolamine (DPPE), and l-α-dipalmitoylphosphatidic acid sodium salt (DPPA), respectively, at the water/chloroform interface. By using pendent drop technique we studied the headgroup effect of lipids on the kinetics of co-adsorption layers. It was found experimentally that a folded drop surface was formed during co-adsorption and the headgroup of lipids affected on the formation rate of the folded drop surface. Such a skinlike film demonstrates that there exits an strong interaction between β-lactoglobulin and each lipid. By depositing one lipid mono- and bilayers onto a solid surface morphology of the mixed lipid/β-lactoglobulin layers has been investigated by atomic force microscopy (AFM).