Shape characterization of polymersome morphologies via light scattering techniques

Abstract

\u3cp\u3ePolymersomes, vesicles self-assembled from amphiphilic block copolymers, are well known for their robustness and for their broad applicability. Generating polymersomes of different shape is a topic of recent attention, specifically in the field of biomedical applications. To obtain information about their exact shape, tomography based on cryo-electron microscopy is usually the most preferred technique. Unfortunately, this technique is rather time consuming and expensive. Here we demonstrate an alternative analytical approach for the characterization of differently shaped polymersomes such as spheres, prolates and discs via the combination of multi-angle light scattering (MALS) and quasi-elastic light scattering (QELS). The use of these coupled techniques allowed for accurate determination of both the radius of gyration (R\u3csub\u3eg\u3c/sub\u3e) and the hydrodynamic radius (R\u3csub\u3eh\u3c/sub\u3e). This afforded us to determine the shape ratio ρ (R\u3csub\u3eg\u3c/sub\u3e/R\u3csub\u3eh\u3c/sub\u3e) with which we were able to distinguish between polymersome spheres, discs and rods.\u3c/p\u3