Biomedical Engineering Reference
In-Depth Information
quantum. dots,
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. as. growth. factor. delivery. materials. for. tissue. engineering,
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. and. for.
gene
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.and.drug
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.delivery.and.transport.purposes.
In.drug.delivery.applications,.nanoparticles.are.preferred.mainly.due.to.their.improved.
bioavailability,. solubility,. and. retention. time.
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. Encapsulation. of. drugs. in. nanoparticles.
increases.the.eficiency.of.the.drug.due.to.improved.localization,.especially.after.extrava-
sation,.a.capability.that.the.microparticles.do.not.have..Moreover,.an.encapsulated.drug.
is.protected.from.early.degradation.while.in.the.circulatory.system,.before.reaching.the.
target.organ.or.tissue..Like.microparticles,.nanoparticles.can.be.designed.to.target.a.par-
ticular.organ.or.tissue.so.that.the.drug.accumulates.at.the.predetermined.area.without.
excessive.dilution.along.the.route.
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.In.addition.to.targeted.release,.controlled.or.respon-
sive. release. can. also. be. achieved. with. nanoparticles.. The. control. factors. can. be. pH,
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.
temperature,
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.and.light.exposure.
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.In.brief,.utilization.of.nanoparticles.in.drug.delivery.
increases.the.therapeutic.value.of.the.drug,.which.then.can.lead.to.lower.risks.and.hos-
pital.costs.
Although.nanoparticles.are.widely.utilized.in.many.areas,.they.may.also.pose.risks.to.
both. human. health. and. the. environment.. These. risks. have. led. to. the. development. of. a.
research.area.called.nanotoxicology,.which.deals.with.the.toxic.effects.of.nanomaterials.
on.living.organisms..Although.nanoparticles.have.been.found.to.be.dispersed.everywhere.
(air,.soil,.and.water),.no.exhaustive.study.has.been.carried.out.concerning.the.long-term.
detrimental.effects.of.nanoparticles.on.the.environment..However,.it.is.known.that.there.
are.various.adverse.health.effects.of.nanoparticles..For.example,.it.is.reported.that.nano-
particles.can.easily.enter.the.body.through.inhalation,.injection,.dermal.route,.and.inges-
tion,.and.these.particles.can.be.accumulated.in.the.tissues.upon.entering.the.body.
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.They.
can. also. migrate. from. these. entry. points. to. the. circulatory. and. lymphatic. systems. and.
ultimately.reach.organs.and.tissues..The.deposition.of.these.nanoparticles.might.lead.to.
inlammation. or. severe. neurological. disorders,. such. as. Parkinson's. or. Alzheimer's. dis-
ease.
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. Nanoparticles. can. also. have. other. effects. as. a. result. of. accumulation. in. organs.
and.tissues..It.would.be.ideal.if.the.nanoparticles.that.have.accomplished.their.function.
were. removed. from. the. body.. Some. can. be. removed. without. any. degradation. process.
(exhalation,.excretion),.while.others.are.metabolized.in.the.body..As.a.consequence.of.the.
degradation.of.these.nanoparticles,.several.by-products,.which.can.also.lead.to.numerous.
complications,.are.formed.
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Depending.on.their.application.areas,.nanosystems.can.be.found.in.different.forms.and.
shapes..They.are.classiied.in.terms.of.dimension,.morphology,.composition,.and.prepara-
tion.approach..Table 11.2.presents.a.schematic.summary.of.nanoparticles.classiied.accord-
ing.to.these.three.categories.
The. nanoparticles. used. in. nanobiotechnology. can. also. be. classiied. according. to. the.
materials.they.are.made.of,.such.as.polymeric,.lipid.based,.and.inorganic:
•.
Polymeric nanoparticles:
. These. nanoparticles. can. be. made. of. either. homo-. or.
copolymers,.and.their.blends.in.different.shapes.(e.g.,.rod,.iber,.sphere,.etc.)..They.
can. be. made. of. degradable. or. nondegradable,. hydrophilic. or. hydrophobic. poly-
mers,. and. can. constitute. the. bulk. or. the. coat. of. the. nanoparticles.. Due. to. their.
nanosize,.they.have.a.high.surface.area-to-volume.ratio,.indicating.that.there.are.
more. molecules. on. the.surface. of. a.nanoparticle. than. in. the.core..Since. the.sur-
face.is.part.of.the.interface.with.the.tissue,.these.molecules.have.the.potential.to.
react.with.the.surrounding.molecules,.which.makes.nanoparticles.proper.tools.for.
