Surface Engineering Research Group, UCD School of Electrical, Electronic and Mechanical Engineering, University College Dublin, Ireland.
J Biomater Appl. 2011 Sep;26(3):327-47. doi: 10.1177/0885328210372148. Epub 2010 Jun 21.
Biomaterials interact with the biological environment at their surface, making accurate biophysical characterization of the surface crucially important for understanding subsequent biological effects. In this study, the surface of polystyrene (PS) was systematically altered in order to determine the effect of plasma treatment and surface roughness on cell adhesion and spreading. Surfaces with water contact angle from hydrophilic (12°) to superhydrophobic (155°) were obtained through a combination of modifying surface roughness (R (a)), the deposition of siloxane coatings and the fluorination of the PS surface. R (a) values in the range of 19-2365 nm were obtained by grinding the PS surface. The nanometer-thick siloxane coatings were deposited using an atmospheric pressure plasma system, while the fluorination of the PS was carried out using a low-pressure radio frequency (RF) plasma. The siloxane coatings were obtained using a liquid poly(dimethylsiloxane) precursor that was nebulized into helium or helium/oxygen plasmas. Water contact angles in the range of 12-122° were obtained with these coatings. Cell adhesion studies were carried out using human MG63 osteosarcoma cells. It was observed that higher polymer surface roughness enhanced cell adhesion, but had a negative effect on cell spreading. Optimum cell adhesion was observed at ∼64° for the siloxane coatings, with a decrease in adhesion observed for the more hydrophilic and hydrophobic coatings. This decrease in cell adhesion with an increase in hydrophobicity was also observed for the fluorinated PS surfaces with water contact angles in the range of 110-155°.
生物材料在其表面与生物环境相互作用，因此准确地对表面进行生物物理特性描述对于理解随后的生物效应至关重要。在本研究中，通过系统地改变聚苯乙烯（PS）的表面，确定等离子体处理和表面粗糙度对细胞黏附和铺展的影响。通过组合改变表面粗糙度（Ra）、硅氧烷涂层的沉积和 PS 表面的氟化，得到水接触角从亲水（12°）到超疏水（155°）的表面。通过研磨 PS 表面，得到 Ra 值在 19-2365nm 范围内的表面。使用大气压等离子体系统沉积纳米厚的硅氧烷涂层，而 PS 的氟化则采用低压射频（RF）等离子体进行。硅氧烷涂层是使用液体聚二甲基硅氧烷（PDMS）前体制备的，该前体被雾化到氦气或氦/氧气等离子体中。通过这种方法，可以得到水接触角在 12-122°范围内的涂层。使用人 MG63 骨肉瘤细胞进行细胞黏附研究。结果表明，较高的聚合物表面粗糙度会增强细胞黏附，但对细胞铺展有负面影响。在硅氧烷涂层中，观察到约 64°时具有最佳的细胞黏附，而对于更亲水和疏水的涂层，黏附力则会降低。对于水接触角在 110-155°范围内的氟化 PS 表面，也观察到随着疏水性的增加，细胞黏附力下降的现象。
