New Full Paper in Small

posted Aug 28, 2012, 6:42 AM by Shin-Hyun Kim   [ updated Sep 1, 2012, 10:24 PM ]
 Shin-Hyun Kim, Jin Woong Kim, Do-Hoon Kim, Sang-Hoon Han, and David A. Weitz, "Polymersomes Containing Hydrogel Network for High Stability and Controlled Release," Small (2012). (accepted for publication)

We use capillary microfluidic devices to prepare monodisperse polymersomes consisting of a hydrogel core and a bilayer membrane of amphiphilic diblock-copolymers. To make polymersomes, water-in-oil-in-water double-emulsion drops are prepared as templates through single-step emulsification in a capillary microfluidic device. The amphiphile-laden middle oil phase of the double-emulsion drop dewets from the surface of the innermost water drop which contains hydrogel prepolymers; this dewetting leads a formation of bilayer membrane. Subsequently, the oil phase completely separates from the innermost water drop, leaving a polymersome. Upon UV illumination of the polymersome, the prepolymers encapsulated within the interior are crosslinked, forming a hydrogel core. The hydrogel network within the polymersomes facilitates sustained release of the encapsulated materials and increases the stability of the polymersomes through formation of a scaffold to support the bilayer. In addition, this approach provides a facile method to make monodisperse hydrogel particles directly dispersed in water.