Observation of cell detachment behavior from temperature responsive polymer grafted surfaces using total internal reflection fluorescence microscopy

PIPAAm grafted coverslip was prepared using electron beam and coverslips modified with MPTMS. ESCA analysis of resulting surfaces revealed that PIPAAm was successfully grafted onto the coverslips. Initial monomer concentration significantly influenced properties of resulting PIPAAm grafted surfaces. PIPAAm grafted coverslips prepared at 5 wt% monomer concentration showed cell attachment and detachment properties in response to temperature. However, cells did not adhere to PIPAAm grafted coverslips prepared at more than 35 wt% concentratioa These phenomena are consistent with wettability of the two surfaces. AFM measurement of the PIPAAm grafited coverslips, which are subjected to locally limited UV laser ablation, demonstrate that the grafted PIPAAm is ultra thin layer. The PIPAAm layer obtained at 5.0 wt% is ca 4.0 nm, while that at 40.0 wt% is ca 8.0 nm We discuss an influence of the basal surfaces onto the grafted PIPAAm on the basis of correlation between cell adhesion / detachment properties and thickness of the grafted PIPAAm.