Sorting catalytically active polymersome nanoreactors by flow cytometry

• Main Authors: Nallani, Madhavan, Woestenenk, Rob, Hans-Peter M. de Hoog, Dongen, Stijn F. M. van, Boezeman, Jan, Cornelissen, Jeroen J. L. M., Nolte, Roeland J. M., Hest, Jan C. M. van.
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Materials::Biomaterials
• Online Access: https://hdl.handle.net/10356/93845; http://hdl.handle.net/10220/7282
• Institution: Nanyang Technological University

Flow cytometry is a powerful technique for high-throughput, fluorescence-activated screening and sorting of cells (FACS). This methodology has been extended by Griffiths to the screening of water-in-oil microdroplets filled with an in vitro protein expression system.[1–6] The catalytic gene product was detected by the transformation of a co-encapsulated profluorescent substrate into a fluorescent product. Here we report a strategy that involves a versatile one-step preparation procedure of enzyme filled porous and stable polymeric capsules (polymersomes). Since the pores of the capsules are small enough to keep enzymes in, whereas these are sufficiently large to allow (profluorescent) substrates to enter, enzyme activity screening can be performed by the build-up of fluorescence, followed by FACS. To prevent the substrate from diffusing out of the capsules, a trapping agent was added inside the capsule. With this technology we were able to separate enzymatically active polymersomes from non-filled or non-active polymersomes.