Santosomes as natural and efficient carriers for the improvement of phycocyanin reepithelising ability in vitro and in vivo

New biocarriers, named santosomes, were formulated using Santolina insularis essential oil and hydrogenated phosphatidylcholine. They were modified by adding propylene glycol, a hydrophylic penetration enhancer, and loaded with phycocyanin, a protein found in cyanobacteria, which possesses antioxidant and antiinflammatory properties. The essential oil was expected to modify the bilayer structure and improve the delivery and efficacy of the protein due to a synergistic effect of the phospholipid and S. insularis terpenes. Santosomes were small in size (∼118 nm), unilamellar and with polyhedral shape. SAXS patterns showed that phycocyanin strongly interacted with the polar heads of the vesicle bilayer. Phycocyanin-loaded vesicles did not show any toxic effect in vitro: cell viability was ∼100% in endothelial cells and ∼120% in keratinocytes, at all the concentrations tested. In addition, phycocyanin-loaded vesicles protected the cells against free radical damage. In vivo studies were performed to evaluate the ability of santosomes to inhibit chemically-induced oedema and inflammation in mice. Results demonstrated that the application of phycocyanin-loaded santosomes produced an evident amelioration of the skin lesion, confirming their great potential for wound healing