Biomedical Engineering Reference
In-Depth Information
(a)
(d)
(b)
(e)
(c)
(f)
FIGURE 11.19
SEM images of particles fabricated with different organic solvents and different polymers:
(a) DCM, (b) acetonitrile, (c) THF, (d) EVAC, (e) PLGA, and (f) PDLA. (Polymer, PCL; airfl ow rate, 20 L/
min; concentration, 3%; fl ow rate, 3 mL/h; needle size, 0.34 mm; voltages of nozzle and ring, 8.8 and 7.1 kV).
(Reprinted from Xie, J.W., Marijnissen, J.C.M., and Wang, C.H.,
Biomaterials
, 27, 3321, 2006. © Elsevier
Science. With permission.)
Bioceramic coatings or fi lms, regarded as the attractive substitute materials in the orthopedic
fi elds, have been deposited onto the metal shaft of hip implant and dental screws to promote cellular
ingrowth and also to reduce the mechanical mismatch between the devices and new tissues. The
bioactive surface coatings or fi lms can help integrate the implants into the body. Some biopolymeric
fi lms or coatings have been deposited on the electrode surface of biosensors to enhance biocompat-
ibility. For example, a protein of the extracellular matrix, collagen, has been successfully deposited
to the metallic biomaterial surface to enhance the bioactivity and biocompatibility [66,67]. Native
biomaterials such as starch, protein, and other biomolecules have also been prepared as fi lm and
coating materials in the fi elds of genomic, proteomic, and clinical analyses, as well as in various
food and pharmaceutical applications.
11.2.8.2.1
Bioceramic Materials
Electrostatic spray deposition, a coating technique developed from electrospraying, was used by
Leeuwenburgh et al. [68] to deposit calcium phosphate (CaP) coatings with a variety of chemical
properties. In the biomedical fi elds, bioceramic coatings are frequently deposited onto the surface of
metallic dental or orthopedic implants to improve the biological performance. The CaP bioceram-
ics are considered as a suitable class of biomaterials for use as a surface coating on titanium metals
because of its similarity to the inorganic component of bone and teeth. It can form bonds between
