Abstract
Purpose
The aim of this study was to develop transferrin-conjugated nanoemulsions utilizing hydrophobic ion pairing for a targeted cellular uptake.
Methods
In the lipophilic phase of nanoemulsion composed of 60% oleic acid, 30% Capmul MCM EP and 10% Span 85, 1% cetyltrimethylammonium bromide (CTAB) and 3% phosphatidic acid (PA) were incorporated. After emulsification, the resulting droplets were decorated with human protein transferrin via hydrophobic ion pairing with PA and characterized regarding droplet size and zeta potential. Subsequently, cellular uptake of transferrin-conjugated nanoemulsion was investigated on Caco-2 and HeLa cell lines and determined by flow cytometry, cell lysis method and live cell imaging using confocal laser scanning microscopy.
Results
The nanoemulsion showed a droplet size of 123.03 ± 2.1 nm and zeta potential of − 54.5 mV that changed because of the surface decoration with transferrin to 182.7 ± 0.2 and + 30.2 mV, respectively. Within the uptake studies utilizing flow cytometry, transferrin-conjugated nanoemulsion showed a 5.2-fold higher uptake in Caco-2 cells and twofold improvement in case of HeLa cells compared with unmodified formulation. The outcome was confirmed visually via live cell imaging.
Conclusion
According to the results, transferrin-conjugated nanoemulsion might be considered as a promising drug delivery system for a selective receptor-mediated drug delivery.
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