Development of novel polyglycerol fatty acid ester-based nanoparticles for the dermal delivery of tocopherol acetate.

Abstract The aim of this study was to develop and evaluate novel polyglycerol fatty acid ester (PGFE)-based nanoparticles (NPs) for the dermal delivery of tocopherol acetate (TA). TA-loaded PGFE-based NPs (PGFE-NPs) were prepared by mixing PGFE, soya phosphatidylcholine (Soya PC), dimyristoylphosphatidylglycerol (DMPG), and TA with film using the film rehydration and extrusion method. The prepared formulations were analyzed by dynamic light scattering (DLS) and small-angle X-ray diffraction (SAXD) and polarization microscopy. An in vitro skin accumulation test was performed with TA under occlusive and non-occlusive applications, using Yucatan micropig (YMP) skin. The size range of the TA-loaded PGFE-NPs was 107–28 nm, and they were encapsulated in 1.6–2.2 mg/mL TA. All formulations were negatively charged and stable for 2 weeks. Under occlusive applications, all formulations induced small amounts of TA accumulation in the epidermis but not in the dermis. However, under non-occlusive applications, all formulations enhanced TA accumulation in the epidermis. Furthermore, only the polyglycerol 4-laurate (PG4L)-based formulation induced dermal TA accumulation with the change in the formulation from a vesicular to bilayer stacked structure following water evaporation under non-occlusive applications. These results indicated that the novel TA-loaded PG4L formulation enabled the dermal delivery of TA in non-occlusive applications.