Instability of self-assembled monolayers as a model material system for macrophage/FBGC cellular behavior

• Published in: Journal of biomedical materials research. Part A 2008-07, Vol.86A (1), p.261-268
• Main Authors: Jones, Jacqueline A., Qin, L. Abby, Meyerson, Howard, Kwon, Il Keun, Matsuda, Takehisa, Anderson, James M.
• Format: Article
• Language: English
• Subjects: Adhesiveness; Apoptosis; Biocompatible Materials - chemistry; Biomedical Engineering - methods; Cell Adhesion; Cell Culture Techniques - methods; contact angles; foreign body giant cell; Giant Cells, Foreign-Body - cytology; Giant Cells, Foreign-Body - metabolism; Humans; instability; macrophage; Macrophages - cytology; Macrophages - metabolism; Materials Testing; Microscopy, Atomic Force; Models, Chemical; Monocytes - cytology; self-assembled monolayers; Surface Properties; Time Factors
• ISSN: 1549-3296; 1552-4965
• DOI: 10.1002/jbm.a.31660

Novel self‐assembled monolayers (SAMs) designed to present homogenous surface chemistries were utilized to further investigate the material surface chemistry dependent macrophage and foreign‐body giant cell (FBGC) behaviors, including macrophage adhesion, fusion, and apoptosis. Contact angle analysis revealed instabilities in the CH3 and COOH terminated SAM surfaces upon incubation in serum‐free media (SFM) at 37°C or under dry, room temperature conditions. Further analysis indicated that the CH3 terminated SAM surface degraded rapidly within 2 h and loss of sufficient SAM units to be comparable to the gold (Au) control surface, within 24 h of incubation in SFM at 37°C. After 5 days of incubation in SFM at 37°C, the contact angles for the COOH terminated SAM surfaces increased markedly. AFM analysis confirmed the desorption of CH3 terminated SAM molecules from the surface with increased roughness and marked appearance of peaks and valleys within 2 h. A decrease in the thickness of the COOH terminated SAM surface also suggests molecular desorption over time. No significant changes in contact angle or AFM analyses were observed on the OH terminated SAM surfaces. Cellular adhesion decreased more rapidly on the Au control and CH3 terminated SAM surfaces in comparison to the other surfaces. However by day 10, cellular adhesion, fusion, and apoptosis were comparable on all SAM surfaces and the Au control. These studies suggest that SAM surfaces may not be suitable for long‐term studies where material dependent properties are investigated. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008