MEDICAL DEVICES BASED ON BIOINSPIRED CERAMICS - Advanced Biomaterials: Fundamentals, Processing, and Applications - page 389

(a)

(b)

Figure 11.23. Typical SEM micrographs and EDS analyses of bioactive glass coating (BG42Y)
on biomorphic SiC after immersion in SBF for 72 h. Longitudinal axis (a) and cross-section
(b) images are shown. The coating processing conditions were: laser energy density 4.17 J/cm 2 ,
repetition rate 10 Hz, substrate temperature 200 °C. From [Borrajo, 2006].

of the PLD-coatings and bulk glasses in simulated body fl uid (SBF), with ion
concentrations and pH nearly equal to those of human plasma [Kim, 2001],
keeping the specimens in an incubator at 36.5 °C for 72 hours.
Figure 11.23 shows the products which originated after the immersion of
beech-based SiC coated with a 30 m glass coating. The SEM micrograph and

EDS spectrum (Figure 11.23a) demonstrate the formation of a calcium phosphate
(CaP) layer on the top of the coating. The presence of the silica-rich layer which
corroborates the bioactivity of the PLD glass coatings deposited on biomorphic
SiC is observed in the SEM cross-section (Figure 11.23b). This fact is the fi rst sign
of the possible bioactivity of this material in vivo [Borrajo, 2006 ].
SEM/EDS analyses of the in vitro tested bulk glasses and of the corre-
sponding PLD coatings after immersion in SBF are shown in Figure 11.24. The
bulk glasses present the three expected layers (CaP-rich, CaP-SiO 2 mixture and
SiO 2 -rich), which correspond to different phases of the chemical routes of the

μ