Cellular Interactions with Photo-Cross-Linked and pH-Sensitive Polymersomes: Biocompatibility and Uptake Studies

Polymeric nanoparticles, specifically polymersomes, are at the leading edge of the rapidly developing field of nanotechnology. However, their use for biological applications is primarily limited by the biocompatibility of the components. Hence, optimization of polymersome synthesis protocols should carefully consider aspects of cellular toxicity. In this work, we investigate the viability of HDF and HeLa cells treated with photo-cross-linked and pH-sensitive polymersomes. We demonstrate how aspects of polymersome preparation conditions such as cross-linking density and UV irradiation time may affect their cytotoxic properties. Additionally, we also study the cellular uptake of our polymersomes into the cell types mentioned

Bottom-up Evolution from Disks to High-Genus Polymersomes

<div><div><div><p>We report the design of polymersomes using a bottom-up approach where the self-assembly of amphiphilic copolymers poly(2-(methacryloyloxy) ethyl phosphorylcholine)–poly(2-(diisopropylamino) ethyl methacrylate) (PMPC-PDPA) into membranes is tuned using pH and temperature. We study this process in detail using transmission electron microscopy (TEM), nuclear magnetic resonance (NMR) spectroscopy, dynamic light scattering (DLS), and stop-flow ab- sorbance disclosing the molecular and supramolecular anatomy of each structure observed. We report a clear evolution from disk micelles to vesicle to high-genus vesicles where each passage is controlled by pH switch or temperature. We show that the process can be rationalised adapting membrane physics theories disclosing important scaling principles that allow the estimation of the vesiculation minimal radius as well as chain entanglement and coupling. This allows us to propose a new approach to generate nanoscale vesicles with genus from 0 to 70 which have been very elusive and difficult to control so far.</p></div></div></div