Controlled fabrication of multicompartmental polymeric microparticles by sequential micromolding via surface-tension-induced droplet formation

Polymeric multicompartmental microparticles have significant potential in many applications due to the capability to hold various functions in discrete domains within a single particle. Despite recent progress in microfluidic techniques, simple and scalable fabrication methods for multicompartmental particles remain challenging. This study reports a simple sequential micromolding method to produce monodisperse multicompartmental particles with precisely controllable size, shape, and compartmentalization. Specifically, our fabrication procedure involves sequential formation of primary and secondary compartments in micromolds via surface-tension-induced droplet formation coupled with simple photopolymerization. Results show that monodisperse bicompartmental particles with precisely controllable size, shape, and chemistry can be readily fabricated without sophisticated control or equipment. This technique is then extended to produce multicompartmental particles with controllable number of compartments and their size ratios through simple design of mold geometry. Also, core-shell particles with controlled number of cores for primary compartments can be readily produced by simple tuning of wettability. Finally, we demonstrate that the as-prepared multicompartmental particles can exhibit controlled release of multiple payloads based on design of particle compositions. Combined, these results illustrate a simple, robust, and scalable fabrication of highly monodisperse and complex multicompartmental particles in a controlled manner based on sequential micromolding.