Kasemo B, Gold J
Department of Applied Physics Chalmers, University of Technology and Göteborg University, 412 96 Göteborg, Sweden.
Adv Dent Res. 1999 Jun;13:8-20. doi: 10.1177/08959374990130011901.
The past decades and current R&D of biomaterials and medical implants show some general trends. One major trend is an increased degree of functionalization of the material surface, better to meet the demands of the biological host system. While the biomaterials of the past and those in current use are essentially bulk materials (metals, ceramics, polymers) or special compounds (bioglasses), possibly with some additional coating (e.g., hydroxyapatite), the current R&D on surface modifications points toward much more complex and multifunctional surfaces for the future. Such surface modifications can be divided into three classes, one aiming toward an optimized three-dimensional physical microarchitecture of the surface (pore size distributions, "roughness", etc.), the second one focusing on the (bio) chemical properties of surface coatings and impregnations (ion release, multi-layer coatings, coatings with biomolecules, controlled drug release, etc.), and the third one dealing with the viscoelastic properties (or more generally the micromechanical properties) of material surfaces. These properties are expected to affect the interfacial processes cooperatively, i.e., there are likely synergistic effects between and among them: The surface is "recognized" by the biological system through the combined chemical and topographic pattern of the surface, and the viscoelastic properties. In this presentation, the development indicated above is discussed briefly, and current R&D in this area is illustrated with a number of examples from our own research. The latter include micro- and nanofabrication of surface patterns and topographies by the use of laser machining, photolithographic techniques, and electron beam and colloidal lithographies to produce controlled structures on implant surfaces in the size range 10 nm to 100 microns. Examples of biochemical modifications include mono- or lipid membranes and protein coatings on different surfaces. A new method to evaluate, e.g., biomaterial-protein and biomaterial-cell interactions--the Quartz Crystal Microbalance--is described briefly.
过去几十年以及当前生物材料和医疗植入物的研发呈现出一些总体趋势。一个主要趋势是材料表面功能化程度的提高，以便更好地满足生物宿主系统的需求。过去的生物材料以及目前使用的生物材料本质上是块状材料（金属、陶瓷、聚合物）或特殊化合物（生物玻璃），可能带有一些额外的涂层（例如羟基磷灰石），而当前关于表面改性的研发指向未来更加复杂和多功能的表面。这种表面改性可分为三类，一类旨在优化表面的三维物理微结构（孔径分布、“粗糙度”等），第二类关注表面涂层和浸渍的（生物）化学性质（离子释放、多层涂层、含生物分子的涂层、可控药物释放等），第三类涉及材料表面的粘弹性性质（或更一般地说是微观力学性质）。预计这些性质会协同影响界面过程，即它们之间可能存在协同效应：生物系统通过表面的化学和形貌组合模式以及粘弹性性质来“识别”表面。在本报告中，将简要讨论上述发展情况，并通过我们自己研究中的一些例子来说明该领域当前的研发情况。后者包括通过使用激光加工、光刻技术、电子束光刻和胶体光刻技术对表面图案和形貌进行微纳加工，以在植入物表面产生尺寸范围为10纳米至100微米的可控结构。生化改性的例子包括在不同表面上的单分子层或脂质膜以及蛋白质涂层。简要介绍了一种评估例如生物材料 - 蛋白质和生物材料 - 细胞相互作用的新方法——石英晶体微天平。
