Polymer Vesicle Characterization Protocol

All organics solvents and chemicals were purchased from Sigma-Aldrich (Sigma-Aldrich Chimie, Saint Quentin Fallavier, France) and Thermo Scientific (Waltham, MA, USA). 1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(lissamine rhodamine B sulfonyl) (Rhodamine-PE) were obtained from Avanti Polar Lipids Inc. (Alabaster, AL, USA). Poly(dimethylsiloxane)-nitrobenzoxadiazole (PDMS-NBD) and poly(dimethylsiloxane)-block-poly(ethylene oxide) (PDMS₃₆-b-PEO₂₃, M_n 4000 g.mol^-1) were synthesized as previously described [20 (link)]. This copolymer is known to spontaneously form polymersomes with a membrane thickness of 9.9 ± 1.6 nm. Cationic switchable lipid (CSL) was synthesized as previously described [16 (link)]. Sucrose, calcein and all other chemicals were purchased from Sigma-Aldrich (Saint Quentin Fallavier, France). ¹H Nuclear Magnetic Resonance spectra were acquired at 298 K on a Bruker Avance I NMR spectrometer operating at 400 MHz, using trimethylsilane (TMS) as the internal standard and deuterated chloroform as solvent. Data were treated with TopSpin 4.0.7 (Bruker BioSpin, Wissembourg, France).