Preparation of poly(acrylamide‐co‐acrylonitrile) grafted glass and thermal stimulated detachment of surface‐attached human immortalized mesenchymal stem cells

Abstract Novel cell culture substrates for non‐invasive‐targeted cell recovery were developed by grafting an upper‐critical‐solution‐temperature (UCST)‐type poly(acrylamide‐co‐acrylonitrile) (PAA) onto a glass substrate as a cell attachment scaffold by surface‐initiated reversible addition‐fragmentation chain‐transfer (Si‐RAFT) polymerization. To optimize the UCST of PAA, the cloud point of the free polymer was first determined. Varying the chain lengths of PAA with an optimized AN‐compositions of 31 mol% followed by Si‐RAFT produced immobilized glass substrate (PAA‐g). The PAA‐g surface became hydrophilic, and the polymer brushes swelled as the temperature increased from 30 to 38°C. In addition, the viscoelasticity of PAA‐g was increased by the polymer brushes swelled. Thermal detachment of PAA‐g attached human immortalized mesenchymal stem cells (hiMSC) was observed by raising the temperature from 30 to 38°C. The polymer brushes length of PAA‐g affects the degree of hiMSC detachment, likely due to the change in viscoelasticity with the polymer brushes length.