(229k) Fabrication of Biodegradable Spheroidal Drug Carriers with Modified Emulsion Solvent Evaporation Technique

Hanieh Safari and Omolola Eniola-Adefeso

Rod-shaped particles have recently gained interest for drug delivery applications evidenced by their reduced immune clearance and improved adhesion efficiency in blood flow relative to spheres. Oil-in-water emulsion solvent evaporation has recently been applied to fabricate poly(lactic-co-glycolic) acid (PLGA) micro-sized spheroids. This method benefits from its simple set up, scalability and large production rate and adaptability to different biodegradable polymers compared to other techniques. However, this method has been limited to rods with the major axis size of greater than 10 µm and minor axis size of greater than 2.0 µm that risks blood vessel occlusion. In this study, we developed a two-step fabrication system enabling stretching of smaller sized droplets by separating the droplet formation and stretching steps. In addition, careful tuning of the oil phase solvent and surface-active molecule is critical to spheroid yield. With our two-step method, we were able to scale down the size of the rods to major axis of 3.0 µm and minor axis of 500 nm, which is equivalent to the volume of 1.0 µm spheres. The rods fabricated with this method have the capability to be used both in vitro and in vivo to study the effect of shape on the efficiency of biodegradable drug carriers.