Preparation and characterization of novel pseudo ceramide-based nanostructured lipid carriers for transdermal delivery of apigenin

In this study, pseudo ceramide-based nanostructured lipid carriers (NLCs) were prepared for the transdermal delivery of apigenin (APG). The characterization of APG-NLC9, 6, and 3 containing pseudo ceramide with 1, 2, and 3 double bonds, respectively, were evaluated. The results showed that the particle size of the NLCs was 139.7–192.5 nm. The entrapment efficiencies were 63.4%, 81.2%, and 84.3% for APG-NLC9, 6, and 3, respectively. The crystallinity of the NLCs was as follows: APG-NLC9 (14.09%) > APG-NLC6 (12.19%) > APG-NLC3 (11.27%). The occlusion effects after 48 h of APG-NLC9, 6, and 3 were measured as 24.8, 24.6, and 25.6, respectively. Also, it was confirmed that APG could be well-entrapped in NLCs using XRD. The in vitro drug release study showed that APG-NLCs exhibited a sustained release pattern, and the release rate increased with the increasing number of double bonds as follows: APG-NLC3 > 6 > 9. In the skin permeation evaluation, APG that penetrated the skin was 20.3%, 24.4%, and 25.2% from NLC9, 6, and 3, respectively. Taken together, the novel NLCs are a functional cosmetic formulation capable of effectively delivering APG by controlling drug release and skin permeability via adjusting the number of double bonds of the pseudo ceramide.