Tuning of Surface Properties of Thin Lipid-Protein Films by Hydrophilic Non-Surface Active Polymers

ABSTRACT

We study the capability of hydrophilic polymers (HPs) to reverse the inhibitory effect of albumin and to restore the surface activity of lipid-protein lung surfactants preparations (LSPs): Curosurf and Survanta. HPs implied are dextran and Polyethylene glycol 10000 (PEG10000). LSPs surface activity is evaluated in Thin Films (monolayer and foam) at the air/water interface. Albumin displaces LSP from the interface and inhibits their ability to sustain low surface tension in monolayers and to form stable thin foam films (FFs). When HPs are added to monolayers they restore the surface activity of LSPs and recover their capability to maintain low dynamic surface tensions. Similarly the inclusion of HPs in foam films results in neutralization of the effect of albumin and in formation of stable, thin (with thickness <17 nm) films with homogeneous surfaces, as in the case of pure LSPs. Our findings permit to search for the answer of the intriguing problem why PEG recovers better the surface activity of Survanta, while Dextran—of Curosurf. Such results might be of major importance for the treatment of Adult Respiratory Distress Syndrome.

Keywords:

• lung surfactant
• surface properties
• hydrophyliic polymers
• albumin
• ARDS