Figure 11.4
228
Bacterial Cellulose
Morphology and Structural Analyses of the
Mineralized Ca-P Phase
The.morphology.of.deposited.minerals.on.BC.templates.was.examined.by.
FE-SEM.(S.4100B,.Hitachi.Co.,.Japan,.and.JEOL,.JSM-6700F,.Japan).operating.
at.an.accelerating.voltage.of.1.5.kV..The.BC.specimens.were.sputter-coated.
with. platinum-paladium. (Pt-Pd). and. platinum. for. the. Hitachi. and. JEOL.
microscopes,. respectively.. Formation. of. the. mineralized. Ca-P. phase. was.
determined. by. Fourier. transform. infrared. spectroscopy. (FTIR). (Spectrum.
2000,. Perkin. Elmer). equipped. with. an. attenuated. total. reflection. (ATR).
accessory.using.a.single.reflection.diamond.crystal.ATR.top.plate..The.Ca:P.
ratio. was. measured. by. inductively. coupled. plasma. atomic. emission. spectroscopy.(ICP-AES).(SPS7800,.Seiko.Instrument,.Japan)..A.known.amount.of.
apatite-deposited. BC. templates. were. soaked. in. 2%. nitric. acid. (HNO 3 ). for.
1 day.to.dissolve.the.Ca-P.mineral,.followed.by.filtration.through.a.0.2.μm.cellulose.acetate.filter.and.dilution.to.a.concentration.of.about.5.ppm.(detectable.
range.by.ICP-AES)..The.determination.of.the.Ca:P.ratios.of.all.samples.was.
based.on.calibration.using.synthetic.hydroxyapatite.(Wako.Pure.Chemical.
Ltd.,.Japan).as.a.standard.(Nge.and.Sugiyama.2007).
BC Templates Soaked in 1.5 SBF
Native.BC,.BC-TEMPO,.and.BC-TEMPO-Ca.were.soaked.in.1.5.SBF.to.study.
the.effect.of.surface.functional.groups.on.apatite.formation.on.respective.BC.
templates.(Nge.and.Sugiyama.2007)..The.SEM.images.of.the.apatite-deposited.
surfaces.of.native.BC.and.BC-TEMPO-Ca.after.21.days.of.soaking.in.1.5.SBF.
are. shown. in. Figure 11.4.. The. island-like. hemispherical. globules. of. apatite.crystals.were.formed.on.the.BC.microfibril.surfaces,.where.the.globule.
sizes. were. clearly. different. between. native. BC. and. BC-TEMPO-Ca,. with.
approximately.3.μm.and.less.than.1.μm,.respectively..From.TEM.observation,.each.apatite.globule.was.composed.of.a.cluster.of.numerous.thin-film.
flakes,.with.a.needlelike.appearance,.with.the.relative.individual.crystal.size.
(a)
(b)
(c)
Figure 11.4
SEM. images. of. apatite-deposited. BC. surfaces:. (a). Native-BC,. (b. and. c). BC-TEMPO-Ca. after.
21 days. of. soaking. in. 1.5. SBF.. Source:. From. Nge. et. al.,. Biopolymers. (ISBN:978-953-307-109-1,.
InTech.,.2010),.345–368,.with.permission.
228
Bacterial Cellulose
Morphology and Structural Analyses of the
Mineralized Ca-P Phase
The.morphology.of.deposited.minerals.on.BC.templates.was.examined.by.
FE-SEM.(S.4100B,.Hitachi.Co.,.Japan,.and.JEOL,.JSM-6700F,.Japan).operating.
at.an.accelerating.voltage.of.1.5.kV..The.BC.specimens.were.sputter-coated.
with. platinum-paladium. (Pt-Pd). and. platinum. for. the. Hitachi. and. JEOL.
microscopes,. respectively.. Formation. of. the. mineralized. Ca-P. phase. was.
determined. by. Fourier. transform. infrared. spectroscopy. (FTIR). (Spectrum.
2000,. Perkin. Elmer). equipped. with. an. attenuated. total. reflection. (ATR).
accessory.using.a.single.reflection.diamond.crystal.ATR.top.plate..The.Ca:P.
ratio. was. measured. by. inductively. coupled. plasma. atomic. emission. spectroscopy.(ICP-AES).(SPS7800,.Seiko.Instrument,.Japan)..A.known.amount.of.
apatite-deposited. BC. templates. were. soaked. in. 2%. nitric. acid. (HNO 3 ). for.
1 day.to.dissolve.the.Ca-P.mineral,.followed.by.filtration.through.a.0.2.μm.cellulose.acetate.filter.and.dilution.to.a.concentration.of.about.5.ppm.(detectable.
range.by.ICP-AES)..The.determination.of.the.Ca:P.ratios.of.all.samples.was.
based.on.calibration.using.synthetic.hydroxyapatite.(Wako.Pure.Chemical.
Ltd.,.Japan).as.a.standard.(Nge.and.Sugiyama.2007).
BC Templates Soaked in 1.5 SBF
Native.BC,.BC-TEMPO,.and.BC-TEMPO-Ca.were.soaked.in.1.5.SBF.to.study.
the.effect.of.surface.functional.groups.on.apatite.formation.on.respective.BC.
templates.(Nge.and.Sugiyama.2007)..The.SEM.images.of.the.apatite-deposited.
surfaces.of.native.BC.and.BC-TEMPO-Ca.after.21.days.of.soaking.in.1.5.SBF.
are. shown. in. Figure 11.4.. The. island-like. hemispherical. globules. of. apatite.crystals.were.formed.on.the.BC.microfibril.surfaces,.where.the.globule.
sizes. were. clearly. different. between. native. BC. and. BC-TEMPO-Ca,. with.
approximately.3.μm.and.less.than.1.μm,.respectively..From.TEM.observation,.each.apatite.globule.was.composed.of.a.cluster.of.numerous.thin-film.
flakes,.with.a.needlelike.appearance,.with.the.relative.individual.crystal.size.
(a)
(b)
(c)
Figure 11.4
SEM. images. of. apatite-deposited. BC. surfaces:. (a). Native-BC,. (b. and. c). BC-TEMPO-Ca. after.
21 days. of. soaking. in. 1.5. SBF.. Source:. From. Nge. et. al.,. Biopolymers. (ISBN:978-953-307-109-1,.
InTech.,.2010),.345–368,.with.permission.