Biomedical Engineering Reference
In-Depth Information
FND.treatment,.even.with.the.FND.concentration.as.high.as.100.μg/mL..These.promising.
results. highlight. that. FNDs. are. biocompatible. and. can. serve. as. ideal. candidates. for.
potential.applications.in.human.stem.cell.research.
25.3.2 Biodistribution and in Vivo Toxicity Studies
Although.several.in.vitro.studies.have.proved.ND.to.be.non-toxic,.the.in.vivo.toxicity.of.
the. nanomaterial. is. still. under. question.. Recently,. there. has. been. an. increasing. concern.
about.the.biocompatibility.of.ND.at.the.animal.level.(Yuan.et.al..2009,.2010,.Marcon.et.al..
2010,.Mohan.et.al..2010a)..Yuan.et.al..have.studied.the.biodistribution.and.fate.of.NDs.in.
vivo. (Yuan. et. al.. 2009).. By. using. NDs. labeled. with.
125
I. radioisotopes,. they. ind. that. the.
particles.with.a.size.of.50.nm.predominantly.accumulate.in.liver.after.intravenous.injec-
tion. to. mice.. Spleen. and. lung. are. also. target. organs. for. NDs.. About. 37%. of. initial. NDs.
are.entrapped.in.liver.and.6%.in.lung.after.0.5.h.post-dose.(Figure.25.5)..High-resolution.
transmission. electron. microscopy. and. Raman. spectroscopy. of. digested. organ. solutions.
conirm.the.long-term.entrapment.of.NDs.in.the.liver.and.lung..However,.no.mice.showed.
any.symptoms.of.abnormality,.such.as.weight.loss,.lethargy,.anorexia,.vomiting,.and.diar-
rhea.during.the.treatment..So.far,.the.reported.results.of.the.biocompatibility.are.in.favor.
of.ND,.compared.with.other.carbon-based.nanomaterials.
As.with.many.other.nanoparticles,.NDs.can.easily.diffuse.in.air.during.manufacturing.
and.processing..It.is.possible.for.these.nanoparticles.to.enter.lungs.and.cause.serious.side.
effects.. Therefore,. it. is. important. to. examine. the. effect. of. these. particles. in. lungs. upon.
administration.. Yuan. et. al.. have. investigated. the. pulmonary. toxicity. and. translocation.
of.NDs.with.the.average.diameter.of.4.and.50.nm,.respectively,.in.mice.after.intratracheal.
instillation.(Yuan.et.al..2010)..Their.studies.show.that.there.is.no.signiicant.difference.in.
weight.gain.and.lung.indices.(deined.as.the.ratio.of.the.wet.weight.of.the.lung.to.the.whole.
body. weight). between. control. and. ND-treated. mice.. Additionally,. biochemical. assays.
reveal. no. substantial. increase. in. alkaline. phosphatase. (ALP). values. of. both. ND-treated.
40
35
8
6
4
2
0
Figure 25.5
Biodistribution.of.
125
I-labeled.NDs.in.mice.at.30.min.after.intravenous.injection..(Reprinted.from.
Diamond. Relat.
Mater
.,.18,.Yuan,.Y.,.Chen,.Y.W.,.Liu,.J.-H.,.Wang,.H.F.,.and.Liu,.Y.F.,.Biodistribution.and.fate.of.nanodiamonds.
in
vivo
,.95-100,.2009..Copyright.2009,.with.permission.from.Elsevier.)
