Abstract
In this work, amphiphilic hyaluronan was synthesized by grafting succinylated N-oleoyl-phytosphingosine via esters bonds. Succinylated N-oleoyl-phytosphingosine (sCER) was first prepared by esterification of hydroxyl moieties of the ceramide with succinic anhydride.
The esterification of hyaluronan was governed by crowding effect. The oligomeric HA-sCER derivatives exhibited a strong self-aggregation as evidenced by a very low critical aggregation concentration (1.9 mu g mL-1), higher pyrene binding constant (K(B)), and the smallest particle size (30 nm) in solution.
The self-aggregation properties demonstrated to be a function of the substitution degree and molecular weight of HA. The prepared derivatives were non-cytotoxic towards cell lines NIH-3T3.
Nanoparticles prepared using oligomeric HA-sCER derivatives improved the penetration of Nile red dye through the stratum corneum due to their smaller size (<=50 nm). The fluorescence intensity localized at the stratum corneum was higher for oligomeric HA-sCER.
A significant inhibition of the pro-inflammatory cytokine interleukin-6 production was observed in vitro in macrophages differentiated from THP-1 cells. These findings showed that HAsCER constituted a promising active ingredient for cosmetics use.