Structure and stability of (fluorocarbon-hydrocarbon-water) emulsions for biomedical applications

Perfluorinated liquids have become key fluids in a wide range of fields due to their chemical inertness, biocompatibility and peculiar physical properties. These range from medical applications, as oxygen carriers in blood... [ view full abstract ]

Perfluorinated liquids have become key fluids in a wide range of fields due to their chemical inertness, biocompatibility and peculiar physical properties. These range from medical applications, as oxygen carriers in blood substitute formulations, fluids in eye surgery and emulsions for liquid ventilation, to technological applications as solvents for biphasic synthesis or lubricants.

In spite of their structural similarity, hydrogenated and fluorinated chains display quite different thermophysical and mechanical properties. Perfluorinated chains are not only highly hydrophobic, but also lyophobic, i.e. they segregate hydrogenated chains.

In this work we will present thermodynamic properties of fluorinated alcohols and their mixtures with hydrogenated alcohols and water. Phase diagrams and excess volumes have been experimentally measured and molecular dynamics simulations have been performed to gain a molecular level insight of the structure of the systems. The mixtures exhibit very complex behaviour that result from a balance between the unfavourable dispersion interactions between hydrogenated and fluorinated chains and preferential hydrogen bonding between unlike species. Understanding these phenomena will ultimately allow the optimization of (fluorocarbon-hydrocarbon-water) emulsions for liquid ventilation and drug delivery.

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