In vitro Characterization of Polyethyleneimine-Oleic Acid Cationic Micelle as a Novel Protein Carrier

Background: Nanotechnology has introduced valuable carriers for vaccine delivery. The success of vaccination depends on many factors, such as the intact and safe presentation of vaccine candidates to immune cells. We have conjugated branched PEI-2k and oleic acid (OL) as the building block of the cationic micelle. We aimed to introduce a novel carrier for vaccine candidates. Materials and Methods: We conjugated polyethyleneimine and OL (POA) to synthesize the building blocks of cationic micelles. The critical micelle concentration (CMC), size and zeta potential of micelles, and their stability in 60 days were determined. Loading, encapsulation efficiency, and in vitro release study were assessed using bovine serum albumin (BSA) as a protein model. Furthermore, the cytotoxicity and hemocompatibility of developed nanosized micelles were evaluated to ascertain the biocompatibility of fabricated micelles. Cell uptake of cationic micelles in the macrophage cell line was also followed up. Results: The conjugation of two polymer parts was confirmed by Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance techniques. The CMC of the developed micelles was around 5.62 x 10(-8) mg/ml, whereas the loading and encapsulation efficiencies were 16.5% and 70%, respectively. The size and zeta potential of the cationic micelles were 96.53 +/- 18.53 nm and 68.3 mV, respectively. The release of BSA from POA micelles after 8 and 72 hours was 8.5% and 82%, respectively. Finally, fluorescence microscopy showed that the prepared micelles were successfully and effectively taken up by RAW264.7 cells. Conclusion: These results may provide a cutting-edge vaccine delivery solution and open up a new avenue for future vaccine research.