xii
Preface
described..The.biotechnological.production.not.only.allows.control.of.the.network.structure,.but.also.the.shaping.and.surface.design.of.the.BNC.implants..
In. postprocessing. steps,. partial. or. total. drying. of. the. implants. can. be. performed,.in.a.vacuum,.by.heating.or.hot.pressing,.or.by.freeze-drying.or.solvent.
exchange..In.addition,.specific.perforation.of.the.material.with.channels.up.to.
300.µm.in.diameter.can.be.reliably.carried.out..By.combining.BNC.with.other.
polymers.or.inorganic.compounds.(such.as.hydroxy. apatite).during.biosynthesis.or.aftertreatment,.anocomposites.are.formed.or.material.surfaces.can.be.
coated.with.BNC..In.addition,.metals.and.metal.oxides.can.be.easily.precipitated.on.the.BNC.nanofiber.network.and.active.agents.of.various.kinds,.such.
as.pharmaceuticals.and.dyes,.can.be.incorporated.reversibly.or.irreversibly.
Chapter. 10. describes. BNC. biomaterials. with. controlled. architectures.
for. tissue. engineering. scaffolds. and. customizable. implants.. Through.
careful. control. of. bacteria. motion,. it. is. possible. to. produce. well-defined,.
three-dimensional.scaffolds.for.tissue.reconstruction..A.particular.focus.is.
the.use.of.electric.fields.to.produce.customized.and.highly.oriented.cellulose.networks.and.also.the.development.of.microvascular.networks.within.
BNC.structures..This.is.the.first.attempt.to.control.a.bottom-up.biofabrication.process.in.three.dimensions..The.manipulation.of.electrokinetic.forces.
acting.upon.a.bacterial.cell.can.produce.complex.cellulose.patterns.on.the.
nanoscale.not.achievable.in.static.culture..The.ability.to.control.the.direction.
of.fiber.orientation.could.be.readily.expanded.to.weave.structures.of.multiple.fiber.layers.by.changing.the.orientation.of.the.applied.electric.field.for.
each.layer..Using.this.method,.structures.could.be.constructed.with.desired.
mechanical. properties. for. a. variety. of. applications. including. tissue. engineering,.microelectromechanical.systems.(MEMS),.textiles,.and.electronics.
BNC. has. been. recently. shown. to. have. the. capacity. to. induce. crystal.
growth..Chapter 11.describes.biomimetic.mineralization.of.apatite.on.BNC..
Strategies.for.the.surface.modification.of.BNC.include.TEMPO.(2,2,6,6-tetramethylpyperidine-1-oxyl)-mediated. oxidation. and. medium. modification.
by.the.addition.of.amino.sugar.N-acetylglucosamine.(GlcNAc).during.biosynthesis..TEMPO-modified.BNC.having.active.carboxyl.functional.groups.
showed.a.faster.nucleation.rate.than.native.BNC.and.GlcNAc-incorporated.
BNC.. It was. found. that. the. ability. to. induce. mineral. nucleation. differed.
according.to.the.BNC.template.surface.structure,.which.strongly.influenced.
the.growth.behavior.of.the.. apatite.crystals.
One.of.the.promising.nonmedical.applications.of.BNC.is.its.use.as.electronic.paper..Since.the.discovery.that.polyacetylene.could.be.doped.to.the.
metallic.state.more.than.three.decades.ago,.an.ever-growing.body.of.multidisciplinary.approaches.to.material.design,.synthesis,.and.system.integration.
cation.of.conductive.polymer.blends..Current.results.concerning.the.chemical.polymerization.of.conducting.polymers.on.BNC.are.presented,.including.
a.brief.remark.on.the.rationale.for.the.use.of.conductive.BNC.blends..This.is.
followed.by.a.discussion.of.their.properties.and.potential.applications.
Preface
described..The.biotechnological.production.not.only.allows.control.of.the.network.structure,.but.also.the.shaping.and.surface.design.of.the.BNC.implants..
In. postprocessing. steps,. partial. or. total. drying. of. the. implants. can. be. performed,.in.a.vacuum,.by.heating.or.hot.pressing,.or.by.freeze-drying.or.solvent.
exchange..In.addition,.specific.perforation.of.the.material.with.channels.up.to.
300.µm.in.diameter.can.be.reliably.carried.out..By.combining.BNC.with.other.
polymers.or.inorganic.compounds.(such.as.hydroxy. apatite).during.biosynthesis.or.aftertreatment,.anocomposites.are.formed.or.material.surfaces.can.be.
coated.with.BNC..In.addition,.metals.and.metal.oxides.can.be.easily.precipitated.on.the.BNC.nanofiber.network.and.active.agents.of.various.kinds,.such.
as.pharmaceuticals.and.dyes,.can.be.incorporated.reversibly.or.irreversibly.
Chapter. 10. describes. BNC. biomaterials. with. controlled. architectures.
for. tissue. engineering. scaffolds. and. customizable. implants.. Through.
careful. control. of. bacteria. motion,. it. is. possible. to. produce. well-defined,.
three-dimensional.scaffolds.for.tissue.reconstruction..A.particular.focus.is.
the.use.of.electric.fields.to.produce.customized.and.highly.oriented.cellulose.networks.and.also.the.development.of.microvascular.networks.within.
BNC.structures..This.is.the.first.attempt.to.control.a.bottom-up.biofabrication.process.in.three.dimensions..The.manipulation.of.electrokinetic.forces.
acting.upon.a.bacterial.cell.can.produce.complex.cellulose.patterns.on.the.
nanoscale.not.achievable.in.static.culture..The.ability.to.control.the.direction.
of.fiber.orientation.could.be.readily.expanded.to.weave.structures.of.multiple.fiber.layers.by.changing.the.orientation.of.the.applied.electric.field.for.
each.layer..Using.this.method,.structures.could.be.constructed.with.desired.
mechanical. properties. for. a. variety. of. applications. including. tissue. engineering,.microelectromechanical.systems.(MEMS),.textiles,.and.electronics.
BNC. has. been. recently. shown. to. have. the. capacity. to. induce. crystal.
growth..Chapter 11.describes.biomimetic.mineralization.of.apatite.on.BNC..
Strategies.for.the.surface.modification.of.BNC.include.TEMPO.(2,2,6,6-tetramethylpyperidine-1-oxyl)-mediated. oxidation. and. medium. modification.
by.the.addition.of.amino.sugar.N-acetylglucosamine.(GlcNAc).during.biosynthesis..TEMPO-modified.BNC.having.active.carboxyl.functional.groups.
showed.a.faster.nucleation.rate.than.native.BNC.and.GlcNAc-incorporated.
BNC.. It was. found. that. the. ability. to. induce. mineral. nucleation. differed.
according.to.the.BNC.template.surface.structure,.which.strongly.influenced.
the.growth.behavior.of.the.. apatite.crystals.
One.of.the.promising.nonmedical.applications.of.BNC.is.its.use.as.electronic.paper..Since.the.discovery.that.polyacetylene.could.be.doped.to.the.
metallic.state.more.than.three.decades.ago,.an.ever-growing.body.of.multidisciplinary.approaches.to.material.design,.synthesis,.and.system.integration.
cation.of.conductive.polymer.blends..Current.results.concerning.the.chemical.polymerization.of.conducting.polymers.on.BNC.are.presented,.including.
a.brief.remark.on.the.rationale.for.the.use.of.conductive.BNC.blends..This.is.
followed.by.a.discussion.of.their.properties.and.potential.applications.