(191cs) Formation of Aggregates in Perfluorocarbon-Based Oxygen Carriers WHEN Diluted on Plasma Expanders

Perfluorocarbon (PFC)
based oxygen carriers
supply the blood function of respiratory gases transport. PFC emulsions do not
have a component that generate oncotic pressure, thus it is mixed with a plasma
expander. However, it generates aggregation. The objective of this study was to
evaluate the influence of plasma expanders and main electrolytes in the emulsion
aggregation.

Three phases of experimentation were carried
out. First, the effect of mixing the PFC emulsion with hydroxyethyl starch (HES)
solution was evaluated. Second, the physicochemical properties of the mixture with
different solutions of chlorine, phosphate, potassium and sodium were studied. Third,
the interaction of bovine serum albumin (BSA) and human serum albumin (HSA)
with components of the PFC emulsion was analyzed.

First, stronger aggregation was observed at
higher concentrations of HES, which was attributed to the amount of
electrolytes in the mixture. This was corroborated in the second phase, where
it was determined that the electrolyte charge is the factor that affects the emulsion
stability causing aggregates and particle size increase. Third, it was
evidenced a different behavior of the emulsion in the presence of BSA and HSA,
the second one being an aggregate forming substance.

In conclusion, it was determined that the
plasma expanders and the electrolyte ions charge generate aggregates when they
are diluted in PFC emulsion. Additionally, the chemical structure of the HSA
interacts with the egg yolk lecithin structure (emulsifier) increasing the
particle size. Further, it is known that electrostatic charges also destabilize
plasma proteins, for this reason, our future work include studying the mixture
of blood, plasma expander and PFC emulsion.