Ai Hua, Lvov Yuri M, Mills David K, Jennings Merilyn, Alexander Jonathan S, Jones Steven A
Department of Biomedical Engineering and Institute for Micromanufacturing, Louisiana Tech University, Ruston, LA 71272, USA.
Cell Biochem Biophys. 2003;38(2):103-14. doi: 10.1385/CBB:38:2:103.
A recently developed method for surface modification, layer-by-layer (LbL) assembly, has been applied to silicone, and its ability to encourage endothelial cell growth and control cell growth patterns has been examined. The surfaces studied consisted of a precursor, with alternating cationic polyethyleneimine (PEI) and anionic sodium polystyrene sulfonate (PSS) layers followed by alternating gelatin and poly-D-lysine (PDL) layers. Film growth increased linearly with the number of layers. Each PSS/PEI bilayer was 3 nm thick, and each gelatin/PDL bilayer was 5 nm thick. All layers were more hydrophilic than the unmodified silicone rubber surface, as determined from contact angle measurements. The contact angle was primarily dictated by the outermost layer. Of the coatings studied, gelatin was the most hydrophilic. A film of (PSS/PEI)4/(gelatin/PDL)4/ gelatin was highly favorable for cell adhesion and growth, in contrast to films of (PSS/PEI)8 or (PSS/PEI)8/PSS. Cell growth patterns were successfully controlled by selective deposition of microspheres on silicone rubber, using microcontact printing with a silicone stamp. Cell adhesion was confined to the region of microsphere deposition. These results demonstrate that the LbL self-assembly technique provides a general approach to coat and selectively deposit films with nanometer thickness on silicone rubber. Furthermore, they show that this method is a viable technique for controlling cellular adhesion and growth.
一种最近开发的表面改性方法——层层(LbL)组装法,已应用于硅胶,并对其促进内皮细胞生长和控制细胞生长模式的能力进行了研究。所研究的表面由一种前驱体组成,先交替沉积阳离子聚乙烯亚胺(PEI)和阴离子聚苯乙烯磺酸钠(PSS)层,随后交替沉积明胶和聚-D-赖氨酸(PDL)层。膜的生长随层数呈线性增加。每个PSS/PEI双层的厚度为3纳米,每个明胶/PDL双层的厚度为5纳米。根据接触角测量结果,所有层都比未改性的硅橡胶表面更亲水。接触角主要由最外层决定。在所研究的涂层中,明胶是最亲水的。与(PSS/PEI)8或(PSS/PEI)8/PSS膜相比,(PSS/PEI)4/(明胶/PDL)4/明胶膜对细胞黏附和生长非常有利。通过使用硅橡胶印章进行微接触印刷,在硅橡胶上选择性沉积微球,成功地控制了细胞生长模式。细胞黏附局限于微球沉积区域。这些结果表明,层层自组装技术为在硅橡胶上涂覆和选择性沉积纳米厚度的薄膜提供了一种通用方法。此外,结果表明该方法是一种控制细胞黏附和生长的可行技术。