Plasmon-resonant particles

In this review chapter we have demonstrated the favorable effects of both Plasmon resonant particles and / or microwaves on both the intensity and glow time of chemiluminescence. In addition, thin metallic films, only a few lO s of nanometers thick, are able to directionally radiate chemiluminescence, as compared to the commonly observed isotropic emission. These technologies allow rapid and high... 

The presence of MEF, MEP and Metal-Enhanced superoxide anion radical generation in the same system seems surprising at first, as these processes are effectively competitive and ultimately provide a route for deactivation of electronic excited states. As recently shown by the authors, simultaneous photophysical mechanisms can be present within the same system when enhanced absorption effects of the fluorophore near to silver are present (i.e. an enhanced excitation rate). In this case, enhanced absorption of Acridine near-to the plasmon resonant particles facilitates MEF, MEP, ME Oa and also Metal-Enhanced superoxide generation simultaneously within the same system. Aaidine showed an enhanced absorption spectra near-to silver, similar to other probes reported by the authors, in essence acridine absorbs more light. ... 

Schultz, D. A., Plasmon resonant particles for biological detection. Current Opinion in Biotechnology 2003, 14, (1), 13-22. 

Since noble metal NPs exhibit localized SPR, these plasmon resonant particles can not only have excellent light to heat conversion efficiencies, as discussed above, but also exhibit some non-thermal phenomena that could modulate the interaction between the carrier molecule and the bioactive molecule to be delivered. For example, Halas and his coworkers demonstrate... 

The highest destruction ratio can be achieved by resonant absorption of laser light. Thereby to activate capsules remotely by laser light of near-IR band it is necessary to use plasmon-resonant particle absorption peak of which concides with laser... 

Rebekah A. Drezek 25.5 Silver Plasmon Resonant Particles for Bioassay ... 

Oldenburg, S.J., Genick, C.C., Clark, K.A., and Schultz, D.A. 2002. Base pair mismatch recognition using plasmon resonant particle labels. Anal. Biochem. 309 109-116. 

DARK FIELD OPTICAL MICROSCOPE DESIGNS FOR PLASMON RESONANT PARTICLE (PRP) DETECTION... 

Apparatus for Individual Plasmon Resonant Particle Spectral Determination... 

Figure 10. Apparatus for individual plasmon resonant particle spectral determination . Reproduced om [35].

Figure 11. Spectrum ofan individual blue, green and red plasmon resonant particle (PRP). Reproduced fixnn [S] with permission fiom the publisher. (Copyright 2000 Natitmal Acadony of Scioices, U.S.A.)...

Plasmon Resonant Particles and other Nanoparticles as Labels for Biomedical Applications... 

Keywords— Localized surface plasmon resonance, particle aggregation, catalytic property, fluorescence resonance enei transfer, biobarcode. 

Under i-polarization light, the optical spectra of 5-nm nanoparticles (Fig. 7A), recorded at various incident angles 0 do not change with increasing 0. They are characterized by a maximum centered at 2.9 cV, which is similar to that observed for isolated particles (Fig. 5B). Flowever, the plasmon resonance peak remains asymmetrical, as observed under nonpolarized light (Fig. 6). 

The appearance of a plasmon resonance is strictly related to a distinct size of the corresponding metal, based on the presence of a confined electron gas that interacts with light and so results in typical colours. Is there also a minimum size where plasmon resonance is no longer possible In any case this must happen if a particle reaches a typical molecular status. There are no longer freely mobile... 

From these examples we may conclude that, as was indicated above, the question of having or not having a quantum confinement in a distinct particle allows different answers. All we may notice in this case is that gold, silver or copper particles of a distinct size must possess confined electron gases, but nanoparticles being too small to show a plasmon resonance cannot be excluded as having no confined electrons. On the contrary, as will be shown later by means of the Auss cluster. 

The branched polysaccharide dextran is assembled with alkanethiol-modified gold nanoparticles and the resulting nanocomposite is then functionalized to facilitate the specific binding of target biomolecules. This biorecognition process can be easily detected by particle plasmon resonance (PPR), based on the optical properties of gold nanoparticles [163]. 

The presence of metallic surfaces or particles in the vicinity of a fluorophore can dramatically alter the fluorescence emission and absorption properties of the fluorophore. The effect, which is associated with the surface plasmon resonance of the metallic surface, depends on parameters such as metal type, particle size, fluorophore type and fluorophore-particle separation. 

In order to investigate this effect, ordered arrays of metallic nano-islands were fabricated on glass substrates by a process of natural lithography using monodisperse polystyrene nanospheres. The metal particle dimensions were tailored in order to tune the plasmon resonance wavelength to match the spectral absorption of the fluorophore. The fluorophore, Cy5 dye, which is widely used in optical immunoassays and has a medium quantum efficiency ( 0.3), was used in this preliminary study of the plasmonic enhancement effect. 

L.A. Lyon, D.J. Pena, and M.J. Natan, Surface plasmon resonance of Au colloid-modified Au films particle size dependence. J. Phys. Chem. B 103, 5826-5831 (1999). 

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