Micro- and Nanotechnology in Tissue Engineering - The Nanobiotechnology - page 501

and. Reyes. 2001).. Toward. the. development. of. better,. more. effective,. and. safer. devices,.
several. aspects. including. material. selection. and. device. design. have. been. examined..
A. wide. variety. of. natural. (Hofmann. et. al.. 2006b). and. synthetic. polymers. (Wang. et. al..
2002,.Vozzi.et.al..2003,.Chen.et.al..2006,.Bettinger.et.al..2008,.Bruggeman.et.al..2008).have.
been.investigated.as.biocompatible/biodegradable.materials.for.building.medical.devices.
and.scaffolds.for.tissue.regeneration..These.scaffolds.have.been.utilized.for.applications.
involving.the.heart.(Engelmayr.et.al..2008),.liver.(Vacanti.et.al..1988,.Bettinger.et.al..2009a),.
retina.(Neeley.et.al..2008),.neural.tissue,.skin,.bone,.and.cartilage..A.general.illustration.is.
depicted.in.Figure.22.1,.where.cells.are.harvested,.cultured,.and.seeded..Scaffolds.serve.
both. as. mechanical. supports. and. shape. modiiers,. while. the. porous. nature. assists. with.
high.mass.transfer.and.waste.removal.(Dvir.et.al..2010).
With. many. advances. in. the. aforementioned. areas. related. to. scaffolds. for. tissue. engi-
neering.over.the.past.three.decades,.cell.sources.have.emerged.as.a.barrier.to.restoration.of.

Growth factors

Seeding in 3D
porous scaffold

c

Matrix

Cells

Small
molecules

Tissue organization

d

Cultivation
in 2D

Nanoparticles

b

Engineered tissue
transplantation

Cell isolation

e a

Figure 22.1
(See companion CD for color igure.) .Illustration.of.a.tissue.engineering.concept.on.cell.seeding.of.ECM.mim-
icking.porous.scaffolds..(a).Cells.are.harvested.from.patients.and.then.cultivated..(b).Cell.expansion.done.in.
vitro..(c).Cell.seeding.in.porous.scaffolds.and.cultured.with.growth.factors,.small.molecules,.and.micro-.and/or.
nanoparticles..(d).The.seeded.constructs.are.cultivated.in.bioreactors.for.optimal.conditions.in.organizing.cells.
into. functioning. tissues.. (e). Transplant. the. functioning. tissue. into. original. hosts. to. help. repair. organs. and.
restore.function..(Reprinted.by.permission.from.Macmillan.Publishers.Ltd.. Nature Nanotechnol ,.Dvir,.T.,.Timko,.
B.P.,. Kohane,. D.S.,. and. Langer,. R.,. Nanotechnological. strategies. for. engineering. complex. tissues,. 6,. 13-22,.
Copyright.2010.)