Biomedical Engineering Reference
In-Depth Information
(a)
(b)
(c)
15 min
45 min
5 h
Microvili
Vacuole
100 nm
2 μm
1 μm
FIGURE 8.1
TEM images show time dependence of TiO
2
uptake (10 μg/mL) by A549 cell lines following
(a) 15 min, (b) 45 min, and (c) 5 h incubation. (Reprinted with permission from Andersson, P. A., Lejon, C.,
Ekstrand-Hammarstrom, B. et al. 2011.
Small
7: 514 -523.)
of released Cu
2+
to the observed toxicity [74-76]. The adverse biological effects of CuO NMs [12]
and nano-sized Ag [77] were explained by their solubility, based on data analysis by measurements
using inductively coupled plasma-mass spectrometry (ICP-MS) relevant techniques or simply on
the comparable toxicity to Cu salts [76,78] such as CuSO
4
. By contrast, it was reported that the
cytotoxic effects related to the released copper fraction were found to be significantly lower than the
effects related to CuO particles [79,80]. There is no directly analytical technique to characterizing
the dissolution of NMs in a cell culture medium. At present, the “free released ion concentration” is
commonly determined by using ICP-based techniques [81,82] to measure the supernatant collected
(a)
3000
2000
1000
S421
0
Raman shift (cm
-1
)
(b)
3000
2000
1000
S440
0
Raman shift (cm
-1
)
(c)
5000
4000
3000
2000
1000
0
Equal
mix
Raman shift (cm
-1
)
FIGURE 8.2
Raman spectroscopy study of Au NPs coated with a layer of Raman-active material (S421 and
S440, Nanoplex Biotags, Oxonical). (a) Raman spectroscopy acquired from first s.c. injection of S421 NPs, (b)
Raman spectroscopy acquired from second s.c. injection of S440, and (c) Raman spectroscopy acquired from
third s.c. injection of an equal mix of S421 and S440. In the right panel, the image designated “Equal mix” was
calculated by the analysis software to represent an equal mix of the S421 and S440 NPs in the map. (Reprinted
with permission from Keren, S. et al.
Proc. Natl. Acad. Sci. USA
105: 5844-5849.)
