One-step controlled precipitation to fabricate glucose-responsive microcapsules

Advanced multi-compartmental concanavalin A (Con A)/glycogen complex microcapsules incorporated with polymeric micelles were successfully fabricated by a facile, one-step controlled precipitation method. Dropwise addition of Con A solution into glycogen solution results in Con A/glycogen complex precipitates, which are captured by polyethyleneimine-modified CaCO₃ microparticles, forming a continuous shell structure. Removal of the carbonate cores yields hollow capsules of Con A/glycogen complex, which have variable sizes and wall thicknesses under different precipitation conditions. The capsules show molecular-recognizable response to glucose and dextran (M _w, 20 and 40 kDa), leading to breakdown of the capsule structure and release of the incorporated substances such as poly(styrene-b-acrylic acid) micelles.