Biomedical Engineering Reference
In-Depth Information
Table 1
Current techniques for micro- and nanoscale biomimetic surface engineering
Method
Material
Resolution
References
Injection molding,
casting, and
embossing
Synthetic polymers
~15 nm
Wilkinson et al.
(
1998
) and
Gadegaard et al.
(
2003
)
Polymer demixing
Polymer blends (e.g.,
polystyrene/
polymethylmethacrylate)
10 nm
Dalby et al. (
2004a,
b
) , Barbucci et al.
(
2003
) , Riehle et
al. (
2003
) , and
Gadegaard et al.
(
2004
)
Electron beam
lithography
Silica, silicon, and polymers
<10 nm
Wilkinson et al.
(
2002
) and
Malaquin et al.
(
2004
)
Colloidal
nanolithography
Gold colloids
50 nm
Arnold et al. (
2004
)
and Wood et al.
(
2002a,
b
)
Peptide-functionalized gold
nanodots
8 nm dot size
Nanopillars on quartz, silicon,
and polymers
20 nm
Microcontact
printing
Biomolecules (proteins and
polysaccharides) and
chemical compounds on a
fl at substrate
100 nm
Wilkinson et al.
(
2002
) and Michel
et al. (
2002a
)
Self-assembling
monolayers
Alkanethiols on gold,
trichlorosilanes on glass,
and silicon
<10 nm
Chen et al. (
2000
) ,
Finnie et al.
(
2000
) , and Smith
et al. (
2004
)
reorganization, signaling, and cell motility (Maheshwari et al.
2000
) . There appears
an optimal spacing of ~70 nm between individual ligands for integrin clustering and
activation (Arnold et al.
2004
). In addition to lateral organization, ligand presenta-
tion in the axis perpendicular to the cell membrane plays an important role. When
RGD peptide is mobilized to the substrate with a polymer spacer, linker length
affects effi ciency of cell attachment, and that the optimal distance between RGD
peptide and substrate has been shown to be ~3.5 nm (Shin et al.
2003
) .
4.3
Brief Survey of Nanofabrication Techniques
While the techniques for nanofabrication have been developing at a very rapid pace
in the last decades, the use of nanomaterials in medicine and biology is quite inno-
vative, and much research needs to be completed before we have a full understand-
ing on nanomaterials and nanostructures. Development of nanomaterials and
nanotechniques relies often on well-established progress in the electronic and opti-
cal engineering fi eld (see Tables
1
and
2
). Several methods have been developed