Microfluidic Production of Alginate Hydrogel Particles for Antibody Encapsulation and Release

Owing to their biocompatibility and reduced side effects, natural polymers represent an attractive choice for producing drug delivery systems. Despite few successful examples, however, the production of biopolymer-based particles is often hindered by considerable technical challenges mainly associated with high viscosity of polymer fluids. In this work, we present a microfluidic approach for production of alginate-based particles carrying encapsulated antibodies. We use a triple-flow microdevice to induce hydrogel formation inside droplets before their collection off-chip. The fast mixing and gelation process produced alginate particles with a unique biconcave shape and dimensions approaching those of mammalian cells. We show slow and fast dissolution of particles in different buffers and record controlled antibody release over time.