ABSTRACT
Biomaterials are central to numerous biomedical and biotechnological applications, including drug delivery, contact lenses, vascular grafts, heart valves, and total joint replacements. Initially, biomaterials were adopted from other areas of science and technology without signi„cant redesign for medical use (Langer and Tirrell, 2004). These early biomaterials include silicones, polyurethanes, Težon®, nylon, titanium, and stainless steel. Although these early biomaterials „lled a gap in medical technology, several limitations still existed. Most signi„cantly, the immune and inžammatory responses to implanted materials resulted in chronically poor integration of the materials within the host tissue
CONTENTS
3.1 Introduction ......................................................................................................................... 95 3.2 Background ........................................................................................................................... 96
3.2.1 Fundamentals of Cell and Matrix Biology ........................................................... 96 3.2.1.1 Cellular Structure and Physiology ......................................................... 96 3.2.1.2 Cell Adhesion Molecules ......................................................................... 98 3.2.1.3 The Extracellular Matrix ........................................................................ 100
3.2.2 Tissue Reaction to Biomedical Materials/Devices ............................................ 102 3.2.2.1 Inžammatory and Immune Responses to Implanted Materials...... 102 3.2.2.2 Inžammatory Responses within the CNS .......................................... 105
3.3 Biomimetic Materials Design ........................................................................................... 108 3.3.1 Bioactive Materials Design: Cell and ECM Mimetic Materials ....................... 109
3.3.1.1 Materials That Facilitate Controlled Protein-Material Interactions............................................................................................... 109
3.3.1.2 ECM Mimetic Materials ......................................................................... 112 3.3.2 Application: Biomimetic Neural Interfaces ........................................................ 115
3.4 Conclusions ......................................................................................................................... 118 Acknowledgment ........................................................................................................................ 119 References ..................................................................................................................................... 119
(Albrektsson et al., 1983; Ziats et al., 1988; Ryd et al., 1995; Bauer and Schils, 1999; Anderson, 2001). Next-generation biomaterials consisted of polymers designed speci„cally for use as biomaterials. Polyesters and polyamides were designed to decrease host immune responses and degrade in vivo through hydrolysis. Although these materials improved on select functions compared with their earlier counterparts, these polymers still lacked the ability to mimic the natural extracellular environment, direct cell function, and facilitate device integration within the native tissue.
