Development and structural characterization of a novel nanoemulsion for oral drug delivery

The objective of this work has been to develop a template for the design and characterization of dried nanoemulsion (NE) for oral administration of hydrophobic compounds. A rational optimization of the nanosystem using an experimental design was performed to achieve stable NE of 100 nm with a neutral surface potential. NE were able to efficiently encapsulate the model drug tacrolimus, providing a sustained drug release in both simulated gastric fluid (SGF) and simulated intestinal fluid in fasted state (FaSSIF-V2). To improve long-term physical stability NE were dried using spray-drying and freeze-drying. Following reconstitution in water, they maintain their physicochemical properties without alteration. The highest process yield was obtained by freeze-drying using very low amount of cryoprotectant overcoming the major challenges related with the production of dry powders from oil based systems.