Illustration of characteristics of (a) poly(N
-isopropylacrylamide) (PIPAAm), (b) temperature-responsive cell culture surface, PIPAAm-TCPS, and (c) cell sheet recovery from PIPAAm-TCPS. (a) PIPAAm chains show reversible temperature-dependent hydration and dehydration across LCST. (b) Above LCST, the grafted PIPAAm chains dehydrated to exhibit enough hydrophobic and cell adhesion properties (right). Below LCST, cells were detached spontaneously from the surface due to hydration of grafted PIPAAm chains (left). These images of (a) and (b) from reference [36
] (Z. Tang and T. Okano., Recent development of temperature-responsive surfaces and their application for cell sheet engineering, Regen Biomater, 1, pp. 91-102) are under a Creative Commons Attribution 4.0 International License (CC-BY-4.0). (c) After adhered cells were confluent at 37°C (left), lowering the temperature to 20°C (below LCST) enabled the detachment of the cell sheet from PIPAAm-TCPS, preserving the deposited ECM and cell-cell junctions (right). Reprinted permission from reference [8
]. Copyright © 2021, Oxford University Press.