Evaluation of polymer and self-assembled monolayer-coated silicone surfaces to reduce neural cell growth

• Published in: Biomaterials 2006-03, Vol.27 (8), p.1519-1526
• Main Authors: Patel, Kruti R., Tang, Haiying, Grever, William E., Simon Ng, Ka Yuen, Xiang, Jianming, Keep, Richard F., Cao, Ting, McAllister, James P.
• Format: Article
• Language: English
• Subjects: Animals; Astrocytes - cytology; Astrocytes - drug effects; Astrocytes - physiology; Biocompatible Materials; Cell Count; Cell Culture Techniques; Cell growth; Cell Proliferation; Cells, Cultured; Cerebrospinal Fluid Shunts; Choroid Plexus - cytology; Choroid Plexus - physiology; Epithelial Cells - physiology; Growth Inhibitors - pharmacology; Heparin - chemistry; Hyaluronic Acid - chemistry; Hydrocephalus - therapy; Hydrocephalus shunts; Hydrophobic and Hydrophilic Interactions; Polymers; Rats; Rats, Sprague-Dawley; Self-assembled monolayer coatings; Silanes - pharmacology; Silicone catheters; Surface Properties
• ISSN: 0142-9612; 1878-5905
• DOI: 10.1016/j.biomaterials.2005.08.009

The development of silicone catheters has improved the treatment of hydrocephalus. Unfortunately, the functionality of the catheters used for the treatment of hydrocephalus is compromised by cell obstruction. In this study silicone surfaces coated with biopolymers (heparin and hyaluronan) and self-assembled monolayers (SAM) (octadecyltrichlorosilane—OTS and fluoroalkylsilane—FAS) were employed to investigate the effect of these coatings on astrocyte and choroid plexus cell growth in vitro. Compared to unmodified silicone, FAS surfaces significantly reduced ( p < 0.05 ) astrocyte proliferation, heparin ( p < 0.001 ) and hyaluronan ( p < 0.001 ) surfaces significantly increased astrocyte growth, while no significant difference was observed on OTS surfaces. A similar trend was observed for choroid plexus cell growth on heparin ( p < 0.05 ) and hyaluronan ( p < 0.05 ) coatings, however, no significant reduction in cell growth was observed on FAS- or OTS-coated surfaces compared to silicone. Low cell growth may be attributed to hydrophobicity of the surfaces (FAS 112.2±2.6°, OTS 102.2±1.3°). Contact angle measurements confirmed the stability of the hydrophobic and hydrophilic properties of all the coatings on the silicone surfaces for 30 days. Surface roughness did not play an important role on cell growth. Silicone shunts coated with SAMs may be suitable for future clinical applications to improve the treatment of hydrocephalus.