Page 468 - Book Hosokawa Nanoparticle Technology Handbook

APPLICATIONS 6 DESIGN OF NANOPARTICLES FOR ORAL DELIVERY OF PEPTIDE DRUGS

0.5 0.09
(A) Ag/TiO _A
2
_B
(B) Ag/TiO 2
0.4 0.06 (C) Ag/TiO _C
2
(D) TiO
2
Absorbance (−) 0.3 (B) (C) Absorbance (−) 0.03
0.2

0
0.1 400 500 600 700 800
Wave length (nm)
(A)
0 Figure 5.9
400 500 600 700 800 Differential spectra of the light absorption characteristics,
before and after the dropping of the ruthenium dye
Wave length (nm)
solution in ruthenium dye/silver nanoparticle/TiO 2
composite film and ruthenium dye/TiO composite film
2
Figure 5.8 (ruthenium surface concentration: 8 10 10 mol/cm ).
2
Light absorption spectra of heat-treated polymer-base
modified silver nanoparticles, ruthenium dye, and
ruthenium dye/silver nanoparticle composite film: Based on these results, we will aim to further
(A) ruthenium dye (ruthenium surface concentration: enhance the efficiency of “A dye-sensitized solar cell
2
1 10 9 mol/cm ); (B) silver nanoparticle; (C) utilizing a metal nanoparticle” employing a silver
ruthenium/silver nanoparticle composite film (ruthenium nanoparticle/dye/titania hybrid film. It would be
2
surface concentration: 1 10 9 mol/cm ) appreciated if you would refer to our findings in our
reports to be issued.
absorption peaks caused by the enhanced absorption
of the dye at 540 nm were observed at around 513 nm, References
thus we succeeded in enhancing the light absorbance
at around 513 nm a maximum of 4 times, or 14 times [1] Nd. K. Nazeeruddin, R. Humphry-Baker, P. Liska and
if the light absorbance of the silver nanoparticle is M. Gratzel: Investigation of sensitizer adsorption and
included. the influence of protons on current and voltage of dye-
Explained are the results whereby the light absorp- sensitized nanocrystalline TiO solar cell, J. Phys.
2
tion of the ruthenium dye was enhanced with the sil- Chem. B, 107(34), 8981–8987 (2003).
ver nanoparticle produced on the quartz substrate via [2] M. Ihara, K. Tanaka, K. Sakaki, I. Honma and
the vacuum vaporization technique or the colloidal
solution for the purpose of enhancing the efficiency K. Yamada: Enhancement of the absorption coefficient
of the dye-sensitized solar cell, and that the light of cis-(NCS) bis(2,2 -bipyridy1-4,4 -dicarboxylate)
2
absorption of the dye in the TiO porous film used for ruthenium(II) dye in dye-sensitized solar cells by a sil-
2
the dye-sensitized solar cell was also enhanced ver island film, J. Phys. Chem. B, 101 (26), 5153–5157
depending on the same effects. (1997).

APPLICATION 6
6 DESIGN OF NANOPARTICLES FOR ORAL DELIVERY OF PEPTIDE DRUGS

Bioavailability of peptide-based pharmaceuticals is becomes significant particularly if the pharmaceutical
extremely low in general because these drugs can be preparations are administered orally. Due to this
easily decomposed by proteolytic enzymes existing in nature, most peptide and protein pharmaceuticals are
the body after their administration. Such a tendency delivered by invasive routes such as subcutaneous

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