AKIYAMA Yoshikatsu    Department   Research Institutes and Facilities, Research Institutes and Facilities    Position   Assistant Professor
Article types	Original article
Language	English
Peer review	Peer reviewed
Title	Comb-type grafted poly(N-isopropylacrylamide) gel modified surfaces for rapid detachment of cell sheet
Journal	Formal name：Biomaterials Abbreviation：Biomaterials ISSN code：01429612
Domestic / Foregin	Foregin
Volume, Issue, Page	31(29),pp.7435-7443
Author and coauthor	Tang Zhonglan†, Akiyama Yoshikatsu, Yamato Masayuki, Okano Teruo*
Publication date	2010/10
Summary	A comb-type grafted poly(N-isopropylacrylamide) (PIPAAm) gel modified surface was newly developed for providing a rapid cell sheet recovery for tissue engineering. PIPAAm macromonomer was prepared by the etherification reaction of the hydroxyl terminal moieties of PIPAAm with acryloyl chloride, followed by the radical telomerization reaction of N-isopropylacrylamide (IPAAm) monomer using 2-mercaptoethanol as a chain transfer agent. Solution containing IPAAm monomer and PIPAAm macromonomer was spread on the surface of tissue culture polystyrene (TCPS), and then the surface was subjected to electron beam irradiation for grafting the monomer and macromonomer on the surfaces, resulting in comb-type grafted PIPAAm gel modified TCPS (GG-TCPS). Besides the difference of the amount of the modified PIPAAm, no distinct difference was found between the properties of GG-TCPSs and normal-type PIPAAm gel modified TCPS (NG-TCPS) through XPS, AFM and a contact angle measurement. At 37 oC, bovine aortic endothelial cells (BAECs) were well adhered and spread on GG-TCPS as well as NG-TCPS regardless of the macromonomer concentration. By lowering temperature to 20 oC, BAECs detached themselves more rapidly from GG-TCPS compared with NG-TCPS. Upon lowering temperature, the grafted polymer was speculated to accelerate the hydration of modified PIPAAm gel, resulting in a rapid cell sheet detachment.
DOI	10.1016/j.biomaterials.2010.06.040