Dynamic Surface Activity of Biological Fluids, Ophthalmic Solutions and Nanostructures

Abstract

Various fluids including tears, pulmonary surfactant and synovial fluid lubricate the surfaces of the body. All have a similar function in that they act as boundary lubricants to prevent focal adhesions and minimize transmittance of shear forces.¹ These fluids also exhibit some remarkable similarities in composition in that they all contain a phospholipid, dipalmitoylphosphatidylcholine, in combination with an amphipathic apoprotein or lipocalin to organize the lipid into lamellar sheets. The challenge in producing replacements for these fluids in treating lubricity deficiency diseases such as dry eye, respiratory distress syndrome and arthritis is not in replacing the phospholipid, which is readily available in synthetic form, but in replacing the apoprotein component.