(789e) Nanoemulsion Composite Microgels: Synthesis and Applications

Polymer hydrogels and microgels have been widely exploited for the controlled storage, delivery and detection of active compounds, including small molecules and biologics. However, due to their intrinsically hydrated microenvironment, the development of hydrogels for encapsulation and/or release of poorly water-soluble cargos remains a persistent challenge. In particular, hydrogel composites that can simultaneously achieve high loading and tunable release for a range of poorly-soluble actives are lacking. As a step towards addressing this problem, we report the synthesis of anisotropic composite microparticles via stop-flow lithography (SFL) containing hydrophobic compartments from photocrosslinkable oil-in-water nanoemulsions. We study the stability of encapsulated nanoemulsions formulated from a variety of silicone and perfluorinated oils. We present proof-of-concept demonstrations of several orthogonal methods, such as hydrophobic anchoring and matrix degradation, by which both hydrophobic and hydrophilic compounds, including small molecules (such as fluorescent dyes, oxygen) and proteins, and the nanoemulsion droplets themselves, can be effectively encapsulated in and released from the resulting microparticles. Unique applications of these composite particles in drug delivery will be discussed.