Menu
Back to Journals » International Journal of Nanomedicine » Volume 6
Cell sheet engineering: solvent effect on nanometric grafting of poly-N-isopropylacrylamide onto polystyrene substrate under ultraviolet radiation
Authors Biazar E , Khorasani MT, Daliri M
Published 2 February 2011 Volume 2011:6 Pages 295—302
DOI https://doi.org/10.2147/IJN.S15371
Review by Single anonymous peer review
Peer reviewer comments 3
Esmaeil Biazar1, MT Khorasani2, M Daliri3
1Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran; 2Biomaterial Department, Iran Polymer and Petrochemical Institute, Tehran, Iran; 3National Research Center for Genetic Engineering and Biotechnology, Tehran, Iran
Background: The best solvent type and ratio for grafting of poly-n-isopropylacrylamide (PNIPAAm) on the surface of polystyrene is obtained under ultraviolet radiation. In this study, the effects of solvents, such as water, methanol, and their combinations, under ultraviolet radiation were investigated successfully.
Method and results: Attenuated total reflection Fourier transform infrared analysis showed the existence of the graft PNIPAAm on the substrate for all samples resolved in solvents. The best solvent ratio and NIPAAm concentration for grafting was obtained with 40% NIPAAm concentrations resolved in a solvent of 9:1 (v/v) water/methanol (120%). Scanning electron microscopic and atomic force microscopic images clearly showed that a 10% increase of methanol to water would increase the amount of grafting. Surface topography and graft thickness in atomic force microscopic images of the grafted samples showed that the thickness of these grafts was about 600 nm. The drop water contact angles of the best grafted sample at 37°C and 4°C were 43.3° and 60.4°, respectively, which demonstrated the hydrophilicity and hydrophobicity of the grafted surfaces. Differential scanning calorimetric analysis also revealed the low critical solution temperature of the grafted sample to be 32°C. Thermoresponsive polymers were grafted to dishes covalently, which allowed epithelial cells to attach and proliferate at 37°C. The cells were also detached spontaneously without using enzymes when the temperature dropped below 4°C.
Conclusion: MTT analysis also showed good viability of cells on the grafted samples, suggesting that this type of grafted material had potential as a biomaterial for cell sheet engineering.
Keywords: nanometric grafting, solvent effect, poly-n-isopropylacrylamide, polystyrene film, ultraviolet radiation
© 2011 The Author(s). This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License.
By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.