Biomedical Engineering Reference
In-Depth Information
ray
opacity. The results of
in vitro
biomineralization studies and MTT assay
depict a better bioactivity of hematite phase compared to the magnetite
phase of iron oxide. The cytotoxicity study also reveals that up to 40 wt% iron
oxide (hematite) in HA is not detrimental to the osteoblast cell activity [101].
Eniu
et al.
reported the magnetic properties of CaO
containing Fe
2
O
3
. All prepared samples were found to retain high X
−
−
P
2
O
5
−
SiO
2
−
Fe
2
O
3
glass
C. These glass samples exhibited the fer-
romagnetic behavior with saturation magnetization ~ 8 Gscm
3
/g after heat
treatment at 1100
−
ceramics sintered at 1500
°
C. The main contributors to magnetization are found to
be iron ions from magnetite Fe
3
O
4
, along with an additional contribution
from
g
°
−
Fe
2
O
3
(maghemite). Also, the EPR studies indicated the presence
of low
sized magnetic domain of iron ions in glass samples [102].
Wu
et al.
developed a multifunctional mesoporous bioactive glass (MBG)
scaffold that is suggested for both hyperthermic as well as local drug deliv-
ery applications [95]. They prepared three MBG
−
−
Fe (MBG, MBG
−
5Fe and
MBG
−
10Fe) scaffolds with a highly porous structure of large pore size (300-
500
like mesopores (4.5 nm), as shown in Figure 7.20.
The MBG scaffolds enclose a well
μ
m) and fi ngerprint
−
organized mesoporous structures
with straight channels (pore size about 5 nm), while MBG
−
−
5Fe and MBG
−
10Fe scaffolds contain built
like
mesopores of size around 4.5 nm. Mechanical properties were not found
to be infl uenced by the addition of Fe into the prepared MBG scaffolds.
The MBG, MBG
−
in curved channels with fi ngerprint
−
−
5Fe and MBG
−
10Fe scaffolds revealed the compressive
strengths 50
±
4.7, 48
±
2.5 and 46
±
5.4 kPa, respectively. In contrast, the
MBG
−
10Fe scaffolds had a well
−
developed hysteresis loop compared to
(
a
)
(
b
)
500
μ
m
500
μ
m
(
c
)
500
μ
m
Figure 7.20
SEM analysis for the MBG scaffolds with different Fe contents.
(a) MBG; (b) MBG
−
5Fe; (c) MBG
−
10Fe [95]. (Copyright (2013), with permission
from Elsevier)
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