Thermo-responsive polymer brushes on glass plate prepared from a new class of amino acid-derived vinyl monomers and their applications in cell-sheet engineering

In this study, we present a novel thermo-responsive polymer platform that is based on the alanine methyl ester-containing homopolymer (PNAAMe) and the copolymer with glycine methyl ester-based vinyl monomer (P(NAAMe-co-NAGMe)) brushes prepared via surface-initiated atom transfer radical polymerization. Water contact angles for these brushes measured at different temperatures reveal that the polymer brushes collapse and dehydrate around 13 degrees C and 25 degrees C (Trs), respectively, upon elevating the temperature. At 37 degrees C, seeded fibroblasts (NIH/3T3) adhere to and spread well onto these brush surfaces although the copolymer brush of P(NAAMe-co-NAGMe) depresses the number of adherent cells less than half of that for the homopolymer of PNAAMe after 24 h of cell culture due to increment in hydrophilicity. To prepare the cell-sheet, the cells are seeded on both polymer brushes and cultured at 37 degrees C in the presence of serum. After 4 days, the cells proliferated confluently on these brush surfaces. Lowering the temperature to 4 degrees C and 20 degrees C below TT of each brush led to the cell-sheet detachment as a monolayer form from the polymer brushes accompanying with the switching of surface affinity. (C) 2017 Elsevier B.V. All rights reserved.