Nanotechnology for biomedical applications - enhancement of photodynamic activity by nanomaterials

Abstract

Abstract. Over the last two decades nanotechnology has become one of the most dynamically evolving field of research. The unique properties of nanomaterials, not disclosing at microscale, are examined and exploited to extend our understanding of the interactions taking place at atomic or molecular level. Those findings affect research in many areas, like e.g. alternative energy sources, electronics, physics and medicine. In this paper, the possibility of using nanomaterials for the enhancement of photodynamic activity, is discussed. A brief review on drug-delivery facilitating nanomaterials, regarding their characteristic features, is presented. An exemplary application of silver-doped nanomaterials for enhancement of photodynamic properties of two photosensitizers: Photolon and Protoporphyrin IX, is described. Influence of silver-doped nanomaterials addition on the fluorescence intensity of photosensitizers immobilized in silica-titania (SiO2-TiO2) sol was examined via VIS spectroscopy. Influence of sonication on the fluorescence enhancement was also investigated. It was demonstrated that the fluorescence enhancement of photosensitizers depends on the concentration of both: photosensitizer and silver-doped nanoparticles.

All‐Carbon Nanotube‐Based Flexible Field‐Emission Devices: From Cathode to Anode

“…Among these silanes, TEOS sol is an attractive option for nanotube binders in field emitters as it does not contain organic materials easily degassed during field emission, and its low curing temperature (less than 150 °C) means it can be applied to flexible polymeric substrates. Furthermore, unlike other silanes, TEOS sol is unfavorable for a hydrophobic nanotube surface because the surface tension of TEOS sol (> 170 mN m −1 ) is larger than that of the CNT wall (∼ 150 mN m −1 ) 34–40. In contrast, a favorable interaction of TEOS with the nanotube tips and defects occurs through hydrogen bonding between hydroxyl groups of the TEOS sol and carboxyl groups of the nanotube tips and defects induced by nitric acid treatment.…”

New Antifouling Platform Characterized by Single-Molecule Imaging

“…In fact, the fluorescence intensity in the presence of 1 nm TiO 2 layer was slightly enhanced compared with the case with the bare quartz surface (Figure 2 a, red versus black symbols), which was probably due to the effect of metal-induced fluorescence enhancement. 21 …”

Applications of titanium dioxide nanoparticles in nanomedicine

“…The principle of PTT depends on the accumulation of TiO2 NPs in cancer cells that will be excited with irradiation of tumor tissue leading to hyperthermia and cell death. Moreover, TiO2 NPs are applied in cancer bioimaging, such as photodynamic diagnosis (PDD) [20].…”