Biomedical Engineering Reference
In-Depth Information
CHAPTER
8
Surface Modification for
Biocompatibility
Erwin A. Vogler
Department of Materials Science and Engineering,
Pennsylvania State University, University Park, PA 16802, USA
Prospectus
The principal motivation behind surface engineer-
ing and modification for improved biocompatibility
of a biomaterial is to control interactions of the
biomaterial with components of living systems or
subsets thereof in a manner that mimics the normal
physiological state or produces a desired change in
biological state. This pursuit of biomimicry is dis-
cussed in this chapter within the context of the core
mechanisms of the biological response to materials. A
tutorial on surfaces, interfaces, and interphases leads
to the identification of specific targets for surface
engineering and modification. These targets include
water wettability (surface energy), surface chemis-
try, surface chemical patterns and surface textures,
and surface presentation of biomimetic motifs. The
chapter concludes with a discussion of the essential
conceptual tools required for building a biomaterials
surface science laboratory, illustrated with an exam-
ple of modifying surfaces for improved cardiovascu-
lar biomaterials.
8.1 INTRODUCTION
8.1.1 The Healthcare Pyramid
Biomaterials are materials used in the fabrication
of medical devices and various tools of modern
biotechnology. Examples include sterile dispos-
ables such as syringes, specimen collection tubes/
plates, and a wide variety of containers used
in animal cell culture and microbiology; tem-
porary implants such as access ports, catheters,
and sutures; and long-term implants generally
intended to service the recipient for a lifetime,
such as dental abutments, heart valves, or ortho-
pedic plates and screws. Collectively, these bio-
medical devices comprise a
healthcare pyramid
when arranged according to volume in use and
technical sophistication, as shown in
Figure 8.1
.
Sterile-disposable medical-procedure devices
are used by the billions worldwide and form the
base of the healthcare pyramid. These devices are
critical components of modern medical practice
and biotechnology. Indeed, sterile disposables and
the biomaterials from which these are fabricated
Keywords
Biocompatibility, Biological response, Biomaterials,
Surface chemistry, Surface energy, Surface engineer-
ing, Surface modification, Surface texture, Wettability
