Membranes auto-réparantes à base de micelles de copolymères à blocs : filtration dynamique et stimulée
Résumé
The chemistry of life is maintained and regulated in vivo via targeted transfer of biocomponents (proteins, DNA, ions) across biological membranes. In medicine, the control of particle trafficking has become crucial in the development of major biotechnologies such as drug carriers, sub cellular sensors, imagers, nanoinjectors, and gene carriers. The biological translocation through the lipid bilayer has a very high specificity enabling a perfect gating process, which has inspired researchers working on synthetic filtration membranes. Despite this exceptional property, biomembranes have a limited application field ex vivo, in particular because of their poor mechanical properties. Herein, we demonstrate the preparation of synthetic translocation membranes, mimicking the lipid bilayer malleability and showing adequate mechanical strength for an industrial application. In this system, a polymer membrane is able to reorganize itself by lateral diffusion of its components to create temporary pores. The autonomous structural adaptation relies on a dynamic assembly of block copolymer micelles enabling to balance the global mechanical properties of the membrane and the dynamism of the translocation stage. In a previous work,[1] membranes consisting of triblock copolymer micelles (poly(styrene-co-acrylonitrile)-b-poly(ethylene oxide)-b-poly(styrene-co-acrylonitrile) (PSAN-PEO-PSAN)) arranged in 3D and interconnected by dynamic copolymer bridges were prepared. While the interstitial space between the spherical micelles enabled the membrane for separating objects, their compressible nature and dynamic bridges interconnecting them demonstrated a pore-size tuning and a self-healing ability. In this work, the micelle network dynamic is used to promote the formation of temporary pores so that an object translocating across this membrane creates a dynamic cavity along its passage, which closes immediately as the object diffuses further across the membrane. Reference : 1. P. Tyagi, A. Deratani, D. Bouyer, D. Cot, V. Gence, M. Barboiu, T. N. T. Phan, D. Bertin, D. Gigmes, D. Quemener, Angewandte Chemie-International, 51, 7166 (2012).