Rapid production of single- and multi-compartment polymeric microcapsules in a facile 3D microfluidic process for magnetic separation and synergistic delivery

A facile liquid-driven compound-fluidic flow focusing (LCFF) platform is employed to produce single- and multi-compartment poly (lactic-co-glycolic acid) (PLGA) microcapsules at high production rates. Single-compartment microcapsules encapsulating magnetic nanoparticles (MNPs) exhibit very good magnetic responsiveness. The magnetic nature allows them to concentrate at specific sites by applying permanent magnetic fields, and the magnetic microcapsules can be separated quickly from the non-magnetic microcapsules. Moreover, multi-compartment microdroplets are produced to encapsulate different kinds of interactive materials individually. It is demonstrated that after the controlled reaction of inner materials, the generated precipitates can be obviously observed. This study provides the LCFF method for one-step preparing uniform-sized single- and multi-compartment microcapsules with solid shell and spherical shape at high throughput, which can be potentially used for several applications, such as sensors, microreactors, diagnostics and drug delivery.