Fluorescence surface-plasmon-enhanced

Robelek R, Stefani FD, Knoll W (2006) Oligonucleotide hybridization monitored by surface plasmon enhanced fluorescence spectroscopy with bio-conjugated core/shell quantum dots. Influence of luminescence blinking. Phys Status Solidi A-Appl Mater Sci 203 3468-3475... 

Figure 5.44 (a) General molecular structure of the porphyrin disulfides, PDSn, described by Ishida and Majima [76]. (b) Changes in the surface plasmon enhanced fluorescence spectra for the exchange reaction of a decane thiol SAM with a 50 mmol dm-31,2-dichloroethane solution of PDS10 (Xem = 725 nm Xex = 425 nm). From A. Ishida and T. Majima, /. Chem. Soc., Chem. Commun., 1299-1300 (1999). Reproduced by permission of The Royal Society of Chemistry... 

Chu L-Q, Forch R, Knoll W (2007) Surface-plasmon-enhanced fluorescence spectroscopy for DNA detection using fluorescently labeled PNA as DNA Indicator . Angew Chem Int Ed 46 4944-4947... 

Y. Zhang, K. Aslan, M. J. Previte, and C. D. Geddes. Metal-Enhanced Fluorescence Surface Plasmons can Radiate a Fluorophores Structured Emission Applied Physics Letters, 2007, 90, 053107. 

Zhang, Y., Aslan, K., Previte, M. J. R., and Geddes, C. D. (2007). Metal-enhanced fluorescence Surface plasmons can radiate a fluorophore s structured emission. Applied Physics Letters 90 053107/053101-053107/053103. 

The periodic arrangement adds two additional fluorescence enhancement mechanisms - increased excitation intensity due to SPP excitation (34) and modification of the radiation emission pattern. The latter effect has been referred to as "beaming" (56), or more appropriately for fluorescence, surface plasmon coupled emission (SPCE) (57), and results from the coupling of multiple nanocavities via the interstitial surface regions. 

Instrumental application of surface-plasmon-enhanced fluorescence was applied in using a TP scanning tunneling microscope [363], This was employed to probe the TP excited fluorescence from organic nanoparticles adsorbed on a silver surface. A size dependence of fluorescence enhancement and photodecomposition was reported as a result of competition between surface-plasmon-enhanced TP fluorescence and nonradiative energy transfer from the excited dye molecules to the silver surface. The schematic experimental setup is shown in Figure 3.14 [363]. 

The detection of DNA hybridization using electrochemical readout is particularly attractive for the development of clinical diagnostics. The use of nanostructured materials in electrical detection for biomolecular sensing offers unique opportunities for electrochemical transduction of DNA sensing events. Tian and co-workers [175] have reported that PANI/Gold nanoparticle multilayer films electrocatalyze the oxidation of nicotinamide adenine dinucleotide (NADH) and detect DNA hybridization by both an electrochemical method and by surface plasmon enhanced fluorescence... 

Fossey and James have also developed a self-assembled boronic acid hybrid system for surface-plasmon-enhanced fluorescence detection of quencher-labeled diols. Snr-face plasmon excitation of the read-out fluorophore has dual advantages firstly, surface plasmon resonance (SPR) may be concomitantly conducted, and no incident light... 

Liebermann T, Knoll W (2003) Parallel multispot detection of target hybridization to surface-bound probe oligonucleotides of different base mismatch by surface-plasmon field-enhanced fluorescence microscopy. Langmuir 9 1567-1572... 

The optimal enhancement effect is observed when the localized surface plasmon resonance is tuned to the emission wavelength of a locally situated fluorophore [86]. This is consistent with the model suggesting a greatly increased efficiency for energy transfer from fluorophores to surface plasmons [78]. Since resonance energy transfer is involved, the important factors affecting the intensity of fluorescence emission must also be the orientation of the dye dipole moments relative to the... 

Alternatively, various analytical methods based on SPR phenomenon have been developed, including surface plasmon field-enhanced Raman scattering (SERS) [7], surface plasmon field-enhanced fluorescence spectroscopy (SPFS) [8-11], surface enhanced second harmonic generation (SHG) [12], surface enhanced infrared absorption (SEIRA) [13], surface plasmon field-enhanced diffraction spectroscopy (SPDS) [14-18], Most of these methods take advantage of the greatly enhanced electromagnetic field of surface plasmon waves, in order to excite a chromophoric molecule, e.g., a Raman molecule or a fluorescent dye. Therefore, a better sensitivity is expected. 

Surface Plasmon Field-Enhanced Fluorescence Spectroscopy... 

Fig. 13. (A) Schematic representation of the interaction between neighboring residues of the His-tag (6 consecutive Histidine residues) and an NTA-complexed Ni2+ ion. (B) The performance of LHCII immobilization via chelating interaction. SPR kinetic curve of LHCII immobilization and regeneration cycles, monitored with an Nd YAG DPSS laser (X = 473 nm). (C) Surface plasmon field-enhanced fluorescence emission spectrum of surface attached LHCII compared with the fluorescence emission from free LHCII in solution, excited by an Nd YAG DPSS laser (X — 473 nm).

Surface plasmon effects result in useful photothermal effects [73] and have been used to enhance the surface sensitivity of various spectroscopic measurements [74], including fluorescence, Raman scattering, and second-harmonic generation. 

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