Biomedical Engineering Reference
In-Depth Information
the surface roughness is closed to a cell size of about 1.0 μm, due
to possible bacteria entrapment [16]. The carbon thin ilm, for
example, has antibacterial characteristics [66], which is very
attractive for biomedical applications. Recently it was reported that
the antibacterial property of stainless steel coated nanocrystalline
diamond ilm was better than titanium [26].
Table 10.1
Examples of applications of carbon biomaterials [12]
Type of material
Function
Type of implant
Area of medicine
Carbon-carbon
composites
Bone ixation
Screws, plates,
nails, stems of
endoprosthesis
Bone surgery
Braided carbon
ibers
Tissue knitting,
reconstruction of joint
ligaments and tendons
Surgical sutures,
ligament and
tendons prosthesis
Orthopedics
Unwoven carbon Filling bone and
cartilage losses
Disks and rings Bone surgery
Coatings of
diamond-like
carbon (DLC)
Coating of metal
implants — corrosion
protection
Joint
endoprosthesis,
screws
Bone surgery
Glassy carbon Blood low regulation Heart valves
Cardiology
To enhance the antibacterial performance of carbon ilms,
the functional doping with luorine, platinum, and silver is useful
[25, 33, 45]. The carbon thin ilm is prepared by chemical vapor
deposition using hydrocarbon gas as the carbon source. Zhou
et al
. [66] investigated the inluence of hydrogen on the antibacterial
performance of carbon ilms, amorphous hydrogenated carbon (a-C:
H) ilm, and hydrogen-free carbon (H-free C) ilm, deposited on the
stainless steel 316L. Figure 10.1 shows the bacterial 24
h incubation
results. The colony numbers of
E. coli
on the hydrogen-free and a-C:
H ilms were reduced to about 15% and 33% of those in the original
316L substrate, respectively [66]. The relatively poor antibacterial
performance of a-C:H ilm compared with H-free carbon ilms is
explained by the degradation of the chemical inertness of carbon
ilm due to hydrogen inclusion. The existence of hydrogen in the
carbon ilm will form the C-H polar bonds, which will promote the
van der Waals force between the polarized surface and the bacteria.
Additionally the low surface free energy support good antibacterial
property [66].
Linares
et al
. [37] found that it is possible to modify activated
carbon with calcium carbonate on microporous carbon. These
modiied carbons with calcium carbonate are able to maintaining a
