Biomedical Engineering Reference
In-Depth Information
15.1 Introduction
As.nanotechnology.and.biotechnology.have.expanded.and.overlapped,.nanotechnology.
has.begun.to.play.a.role.in.an.increasing.number.of.areas.of.biotechnology..In.this.chapter,.
we. explore. the. role. of. nanotechnology. in. bioprocessing.. Bioprocessing. can. broadly.
be. described. as. the. biological. transformation. of. materials. into. desired. end. products.. It.
includes.enzymatic.biocatalysis,.fermentation,.and.mammalian.cell.culture.for.production.
of.therapeutic.proteins.and.high.value.small.molecules,.and.the.associated.bioseparations.
needed.to.obtain.products.of.adequate.purity.for.the.ultimate.application..Bioprocessing.
is. a.multi-billion-dollar-a-year. industry,. with. growth. rates.in.some.sectors.of.up. to.20%.
annually.. In. addition. to. providing. novel. therapeutics. that. have. revolutionized. much. of.
health.care,.bioprocessing.will.play.a.critical.role.in.providing.clean.energy.for.the.twenty-
irst.century.
In.this.chapter,.we.irst.discuss.the.nanoscale.materials,.both.inorganic.and.organic.that.
play.a.role.in.bioprocessing.and.then.focus.on.the.use.of.nanotechnology.in.three.different.
applications—enzymatic. biocatalysis,. bioseparations,. and. microbial. and. mammalian.
cell. culture.. While. it. is. impossible. to. comprehensively. describe. every. application. of.
nanotechnology.in.bioprocessing,.we.hope.to.provide.a.broad.overview.of.the.intersection.
of.these.two.technologies.and.a.vision.of.where.the.future.may.lie.
15.2 Materials
15.2.1 inorganic Materials
An.inorganic.substance.can.be.described.as.a.material.that.is.composed.of.minerals.and.
does.not.contain.carbon.or.other.organic.compounds..Inorganic.materials.have.been.used.
in. conjunction. with. biological. applications. for. many. years.. Inorganic. materials. are. of.
increasing.interest.in.the.biological.ields.when.compared.with.organic.materials.because.
they.are.reusable,.have.higher.mechanical.strength,.and.high.resistivity.to.heat,.chemicals,.
and.microbial.degradation.(Michaels.1990)..Gold,.silicon.(silica),.and.metal.oxides.are.some.
of.the.many.types.of.inorganic.materials.currently.used.for.biological.nanotechnology.
15.2.1.1 Gold
One.of.the.earliest.known.forms.of.nanotechnology.was.the.use.of.colloidal.gold.for.color-
ing.ceramics.and.for.the.production.of.ruby.glass.around.the.ifth.and.fourth.century.BCE.
(Daniel.and.Astruc.2004)..Although.this.technique.is.still.used.today,.colloidal.gold,.also.
known.as.gold.nanoparticles.(AuNPs),.are.now.being.used.for.various.other.applications,.
including.nanobiotechnology.
Gold.has.many.desirable.characteristics.that.make.it.useful.for.many.nanotechnology.
applications..In.the.case.of.biology,.AuNPs.have.many.advantages..One.major.advantage.
is.that.gold.is.very.biocompatible..Shulka.et.al..(2005).showed.that.gold.is.noncytotoxic.and.
nonimmunogenic.to.cells.by.investigating.the.endocytotic.uptake.of.AuNPs.in.RAW264.7.
macrophage.cells.using.different.microscopy.techniques:.atomic.force.microscopy.(AFM),.
confocal-laser-scanning. microscopy. (CLSM),. and. transmission. electron. microscopy.
(TEM).. They. determined. through. these. methods. that. AuNPs. did. not. cause. secretion. of.
