Feature of thermoresponsive polymers grafted on hydrophilic surfaces and recovery of the cell sheet using the the surface

We investigated surface properties of PIPAAm grafted onto hydrophilic PAAm surfaces (PIPAAm-PAAm-TCPS), using electron beam irradiation. In advance, the PAAm grafted onto TCPS was prepared as hydrophilic surfaces. Amount of the grafted PIPAAm and PAAm was measured by FT-IR / ATR spectra. For PIPAAm-PAAm-TCPSs obtained in the present report, wettability (cos q) of resulting surfaces increased with an increase in the grafted PAAm. In the case of the grafted PIPAAm = ca. 1.2 μg/cm², cells adhere to the surfaces of PIPAm-PAAm-TCPS below the grafted PAAm = 0.30 μg/cm², while they did not adhered to the surfaces more than 0.33 μg/cm² of the grafted PAAm. The120PIPAAm-022PAAm-TCPS (the grafted PIPAAm and PAAm are 1.2 and 0.22 μg/cm², respectively) exhibited cell attachment behavior equivalent to PIPAAm grafted TCPS (1.2 μg/cm²). After cells reached conflueency, by lowering temperature, cell sheet was recovered from the120PIPAAm-022PAAm-TCPS surfaces more rapidly than the PIPAAm grafted TCPS. These results suggest that small amount of the grafted PAAm possibly contribute to the rapid cell detachment.