Microfluidic Fabrication of Monodisperse Biocompatible and Biodegradable Polymersomes with Controlled Permeability
Original entry by Bryan Weinstein, Fall 2012
Authors: Shum, H. C., Kim, J.-W., & Weitz, D. A.
Encapsulation and delivery of small amounts of materials such as drugs and fragrances are important to many industries (i.e. pharmaceutical and cosmetic). Encapsulating structures should capture the appropriate material as cost-effectively as possible and should easily be triggered to release the material.
In nature, vesicles naturally encapsulate and release materials. The membrane of a vesicle is created by "amphiphilic molecules" (phospholipids) via self-assembly. Unfortunately, the membrane generally only has a thickness on the order of nanometers, resulting in poor rigidity and a "high water permeation rate" resulting in a short lifetime. Vesicles are thus not ideal candidates to transport materials.
However, synthetic vesicles have been manufactured with amphiphiles of diblock copolymers, or "polymersomes," which have thicker membranes. These vesicles have much better mechanical stability and thus much longer lifetimes. Polymersomes are thus an excellent candidate to transport small amounts of material.
 Shum, H. C., Kim, J.-W., & Weitz, D. A. (2008). Microfluidic fabrication of monodisperse biocompatible and biodegradable polymersomes with controlled permeability. Journal of the American Chemical Society, 130(29), 9543-9. doi:10.1021/ja802157y