A novel phase inversion-based process for the preparation of lipid nanocarriers

Purpose. To develop and subsequently evaluate a novel phase inversion-based method used to formulate lipidic nanocapsules. Methods. Mechanical properties of emulsions prepared by multi-inversion phase processes were investigated using a drop tensiometer. Based on the results obtained, a formulation process was developed and a new type of nanocarrier was prepared. These particulates were sized by photon correlation spectroscopy and were visualized by atomic force microscopy and transmission electronic microscopy. Differential scanning calorimetry was also performed. Results. The marginally cohesive but stable interfacial properties of the initial system led to the formulation of lipidic nanocapsules that were composed of a liquid core surrounded by a cohesive interface and were dispersed in an aqueous medium. These related suspensions were stable upon dilution for several months. The control of the formulation parameters allowed an adjustment of the particle mean diameter in the range of 25-100 nm with a monodisperse size distribution. Conclusions. A novel and convenient process for the preparation of lipidic nanocapsules is described. The structure of these particulates resembles a hybrid between polymeric nanocapsules and liposomes. Such nanocapsules display a strong potential for drug delivery.