Fluorosurfactants for medical nanoemulsions, their surface-active and biological properties

Nano- and microemulsions have found various applications in pharmaceutical and medical areas both in research field as well as in applied solutions for drug delivery or diagnostic agents. However, production of stable and bio- / hemocompatible nanoemulsions are still challenging. New group of ionic surfactants have been synthesized with perfluorohexyl- or perfluorooctyl-groups as hydrophobic tail. The CMC and the parametres of the O/W emulsion (the particle size distribution and the zeta-potential) were determined. The influence of the surfactants on in vitro proliferation of human endothelial cell lines HMEC-1, murine fibroblasts L929 and hemolysis were investigated as characteristic for biocompatibility. Three candidates of surfactants were selected for pre-clinical tests on a small animal model (adult Sprague Dawley rats) on the basis of preliminary studies. This allowed to obtain nanoemulsions with narrow droplets size (average droplet diameter 141-147 nm with PDI index 0.059 - 0.065) and showed better stability over time in comparison to the commercially available surfactants. Neither cytotoxic nor hemolytic potential were observed during incubation of obtained fluorosurfactans with model cell lines L929 and HMEC-1 (average cell viability above 85 % after incubation with 1% solutions) and erythrocytes (hemolysis rate below 3.1 % for all 0.5 % solutions). During acute toxicity test on rat model, it was found that all three tested surfactant solutions showed no significant differences in controlled parameters and survival rate with control group (p > 0.05). Presented surfactants are dedicated but not limited to emulsification of organic fluorocompounds.