Characterization of poly(N-isopropylacryldmide) grafted polydimethylsiloxane surface as a new temperature-responsive cell culture substrate

Our group has developed new type of temperature responsive cell culture surfaces (TRCS), which had mechanical stretchable character, in order to control PIPAAm graft density, graft polymer thickness and surfaces wettability by mechanical stretching and shrinking poly(N-isopropylacrylamide) (PIPAAm) grafted polydimethylsiloxane (PDMS) surfaces (PI-PDMS). PDMS was utilized as a stretchable substrate. Grafting PIPAAm on the PDMS surfaces at non-stretched state was carried out by electron beam (EB) irradiation. Fourier transform infrared spectroscopy / attenuated total reflection (FT-IR / ATR) and X-ray photoelectron spectroscopy (XPS) demonstrated successful grafting of PIPAAm. Stretching PI-PDMS surfaces resulted in decreasing polymer graft density and increasing contact angles of the surfaces. In addition, slower cell detachment behavior was observed in stretched PDMS surfaces. These results suggested that properties of the PI-PDMS surfaces might be controlled by mechanical stretching. One PIPAAm-PDMS might attain fabrication of cell sheets derived from various types of tissue and organ by controlling and stretching PIPAAm-PDMS surface.