Stimuli-responsive polymer layers for advanced cell culture technologies

A series of graft copolymers consisting of poly(N-isopropylacrylamide) as a thermoresponsive component in the polymer backbone and poly(ethyleneglycol) side chains were immobilized as thin films on various substrates via low-pressure plasma treatment. The surface-immobilized hydrogels exhibit a transition from partially collapsed to completely swollen, which is in the range of 32-35 degrees C and corresponds to the lower critical solution temperature of the soluble polymers. Cell culture and detachment experiments were performed with mouse fibroblasts and human corneal endothelial cells under standard conditions. The hydrogel-coated supports were found to permit adhesion, spreading and proliferation of the cells and allowed for fast and effective temperature-dependent detachment of intact cell sheets of both cell types. Thus, these coatings offer an efficient method for growth and gentle harvesting of functional cellular assemblies for use in tissue engineering strategies.