アキヤマ　ヨシカツ   Akiyama Yoshikatsu   秋山　義勝    所属   医学研究科 医学研究科 (医学部医学科をご参照ください)    職種   講師
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Ultrathin poly(N-isopropylacrylamide) grafted layer on polystyrene surfaces for cell adhesion/detachment control
掲載誌名	正式名：Langmuir ISSNコード：0743-7463
掲載区分	国外
出版社	American Chemical Society
巻・号・頁	20(13),pp.5506-5511
著者・共著者	AKIYAMA Yoshikatsu, KIKUCHI Akihiko, YAMATO Masayuki, OKANO Teruo
発行年月	2004/05/26
概要	We investigated physicochemical properties of two types of poly(N-isopropylacrylamide) (PIPAAm)-grafted tissue culture polystyrene (TCPS) surfaces, to elucidate the influential factors for thermally regulated cell adhesion and detachment to PIPAAm-grafted surfaces. The two types of PIPAAm-grafted surfaces were prepared by the electron beam polymerization method. Attenuated total reflection Fourier transform infrared spectroscopy revealed that amounts of the grafted polymers were 1.4 ± 0.1 μg/cm2 for PIPAAm-1.4 and 2.9 ± 0.1 μg/cm2 for PIPAAm-2.9. Both PIPAAm-grafted surfaces showed hydrophobic/hydrophilic property alterations in response to temperature. However, PIPAAm-1.4 surfaces were more hydrophobic (cos θ = 0.21 at 37 °C and cos θ = 0.35 at 20 °C) than PIPAAm-2.9 (cos θ = 0.42 at 37 °C and cos θ = 0.50 at 20 °C) both above and below the PIPAAm's transition temperature. Thicknesses of the grafted PIPAAm layers were estimated to be 15.5 ± 7.2 nm for PIPAAm-1.4 and 29.5 ± 8.4 nm for PIPAAm-2.9, by the use of UV excimer laser and atomic force microscope. Bovine carotid artery endothelial cells (ECs) adhere to the surfaces of PIPAAm-1.4 and proliferate to form confluent cell monolayers. The cell monolayers were harvested as single cell sheets by temperature decrease from 37 to 20 °C. On the contrary, ECs did not adhere to the surfaces of PIPAAm-2.9. This phenomenon was correlated with an adsorption of cell adhesion protein, fibronectin, onto surfaces of PIPAAm-1.4 and -2.9. In the case of nano-ordered thin grafted surfaces, the surface chain mobility is strongly influenced by the thickness of PIPAAm grafted layers because dehydration of PIPAAm chains should be enhanced by the hydrophobic TCPS surfaces. PIPAAm graft amounts, that is, thickness of the PIPAAm grafted layers, play a crucial role in temperature-induced hydrophilic/hydrophobic property alterations and cell adhesion/detachment behavior.
DOI	https://doi.org/10.1021/la036139f