Preparation of Poly(N-isopropylacrylamide) Grafted Polydimethylsiloxane by Using Electron Beam Irradiation
Yoshikatsu Akiyama, Masayuki Yamato, and Teruo Okano
Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University (TWMU), 8-1 Kawadacho, Shinjuku, Tokyo 162-8666, Japan
A poly(N-isopropylacrylamide) (PIPAAm) grafted poly(dimethylsiloxane) (PDMS) surface was prepared as a temperature-responsive cell culture surface by using electron beam (EB) irradiation. Different chemical treatments to modify the bare PDMS surface were investigated for subsequent grafting of PIPAAm, and treatment conditions were optimized to prepare the temperature-responsive cell culture surface. The PDMS surface was initially activated to form silanol groups with conventional O2 plasma or hydrochloric acid (HCl) treatment. Activated PDMS surfaces were individually immobilized with three different conventional silane compounds, i.e., 3-mercaptopropyltrimethoxysilane (MerTMS), 3-methacryloxypropyltrimethoxysilane (MetTMS), and 3-aminopropyltrimethoxysilane (AmiTMS). O2 plasma treatment made PDMS more hydrophilic. In contrast, PDMS surfaces activated with HCl treatment were relatively hydrophobic. Observation of the activated PDMS surface modified with MerTMS, MetTMS, and AmiTMS indicated that these silane compounds had been favorably immobilized on plasma-treated PDMS surfaces. FT-IR/ATR analysis demonstrated that immobilized silane compounds enabled PIPAAm grafting on the PDMS surface. Cell attachment and detachment analysis also suggested that the PDMS surface sequentially treated with O2 plasma and AmiTMS compound was a substrate appropriate for preparing a temperature-responsive cell culture surface by EB irradiation-induced PIPAAm grafting method. The intelligent surface may further be applied to mechanically stretchable temperature-responsive cell culture surfaces.
-  K. Nagase, J. Kobayashi, and T. Okano, “Temperature-responsive intelligent interfaces for biomolecular separation and cell sheet engineering,” J. of The Royal Society Interface, Vol.6, Suppl. 3, pp. S293-S309, 2009.
-  Z. Tang, Y. Akiyama, and T. Okano, “Temperature-Responsive Polymer Modified Surface for Cell Sheet Engineering,” Polymers, Vol.4, No.3, pp. 1478-1498, 2012.
-  Y. Akiyama et al., “Ultrathin Poly(N-isopropylacrylamide) Grafted Layer on Polystyrene Surfaces for Cell Adhesion/Detachment Control,” Langmuir, Vol.20, No.13, pp. 5506-5511, 2004.
-  K. Fukumori et al., “Characterization of Ultra-Thin Temperature-Responsive Polymer Layer and Its Polymer Thickness Dependency on Cell Attachment/Detachment Properties,” Macromolecular Bioscience, Vol.10, No.10, pp. 1117-1129, 2010.
-  Z. Tang et al., “Shear stress-dependent cell detachment from temperature-responsive cell culture surfaces in a microfluidic device,” Biomaterials, Vol.33, No.30, pp. 7405-7411, 2012.
-  J. Zhou, A. V. Ellis, and N. H. Voelcker, “Recent developments in PDMS surface modification for microfluidic devices,” Electrophoresis, Vol.31, No.1, pp. 2-16, 2010.
-  T. Sun and G. Qing, “Biomimetic smart interface materials for biological applications,” Adv Mater, Vol.23, No.12, pp. H57-77, 2011.
-  J. Zhou et al., “Surface modification for PDMS-based microfluidic devices,” Electrophoresis, Vol.33, No.1, pp. 89-104, 2012.
-  A. Kikuchi et al., “Two-dimensional manipulation of confluently cultured vascular endothelial cells using temperature-responsive poly(N-isopropylacrylamide)-grafted surfaces,” J. Biomater. Sci. Polym. Ed., Vol.9, No.12, pp. 1331-1348, 1998.
-  S. Iwanaga et al., “Fabrication of a cell array on ultrathin hydrophilic polymer gels utilising electron beam irradiation and UV excimer laser ablation,” Biomaterials, Vol.26, No.26, pp. 5395-5404, 2005.
-  J. A. Vickers, M. M. Caulum, and C. S. Henry, “Generation of Hydrophilic Poly(dimethylsiloxane) for High-Performance Microchip Electrophoresis,” Analytical Chemistry, Vol.78, No.21, pp. 7446-7452, 2006.
-  H. Huang et al., “Characterizing Polymer Brushes via Surface Wrinkling,” Chemistry of Materials, Vol.19, No.26, pp. 6555-6560, 2007.
-  N. Yamada et al., “Thermo-responsive polymeric surfaces; control of attachment and detachment of cultured cells,” DieMakromolekulare Chemie, Rapid Communications, Vol.11, No.11, pp. 571-576, 1990.
-  I. V. Tetko and P. Bruneau, “Application of ALOGPS to predict 1-octanol/water distribution coefficients, logP, and logD, of AstraZeneca in-house database,” J. of Pharmaceutical Sciences, Vol.93, No.12, pp. 3103-3110, 2004.
-  V. Roucoules et al., “Changes in Silicon Elastomeric Surface Properties under Stretching Induced by Three Surface Treatments,” Langmuir, Vol.23, No.26, pp. 13136-13145, 2007.
-  Z. Wu and K. Hjort, “Surface modification of PDMS by gradientinduced migration of embedded Pluronic,” Lab on a Chip, Vol.9, No.11, pp. 1500-1503, 2009.
-  D. Ma et al., “Preparation and characterization of thermoresponsive PDMS surfaces grafted with poly(N-isopropylacrylamide) by benzophenone-initiated photopolymerization,” J. of Colloid and Interface Science, Vol.332, No.1, pp. 85-90, 2009.
-  A. J. Satti et al., “Modelling molecular weight changes induced in polydimethylsiloxane by gamma and electron beam irradiation,” European Polymer J., Vol.44, No.5, pp. 1548-1555, 2008.
This article is published under a Creative Commons Attribution-NoDerivatives 4.0 International License.
Copyright© 2013 by Fuji Technology Press Ltd. and Japan Society of Mechanical Engineers. All right reserved.