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Surface label-enhanced

Can one further enhance the performance of this classically promoted Rh catalyst by using electrochemical promotion The promoted Rh catalyst, is, after all, already deposited on YSZ and one can directly examine what additional effect may have the application of an external voltage UWR ( 1 V) and the concomitant supply (+1 V) or removal (-1 V) of O2 to or from the promoted Rh surface. The result is shown in Fig. 2.3 with the curves labeled electrochemical promotion of a promoted catalyst . It is clear that positive potentials, i.e. supply of O2 to the catalyst surface, further enhances its performance. The light-off temperature is further decreased and the selectivity is further enhanced. Why This we will see in subsequent chapters when we examine the effect of catalyst potential UWR on the chemisorptive bond strength of various adsorbates, such as NO, N, CO and O. But the fact is that positive potentials (+1V) can further significantly enhance the performance of an already promoted catalyst. So one can electrochemically promote an already classically promoted catalyst. [Pg.19]

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... [Pg.154]

Medlin et al. studied the epoxidation of deuterium-labeled 1,3-butadiene to epoxybutene (EpB) on unpromoted and cesium-promoted silver catalysts and found parallel results to those obtained by Cant and Hall for ethylene epoxidation [370]. Again, it was observed that deuterium-labeling enhanced epoxide formation and this suggested the involvement of a common surface intermediate leading to both EpB and CO2. In particular, it was found that the kinetic isotope effect was significant only when D was incorporated in the 1- and 4-positions, suggesting that combustion was initiated by the cleavage of a terminal C-H bond. [Pg.41]

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... [Pg.1330]

Granqvist, N., Harming, A., Eng, L Tuppurainen, J., and Viitala, T. (2013) Label-enhanced surface plasmon resonance a new concept for improved performance in optical biosensor analysis. Sensors (Basel), 13 (11), 15348-15363. [Pg.421]

Next, we attempted to deal with translocation of foliar-applied TCDD. Labeled dioxins were applied to the center leaflet of the first trifoliate leaf of 3-week-old soybean plants and the first leaf blade of 12-day-old oat plants. All compounds were applied in an aqueous surfactant solution (Tween 80) to enhance leaf adsorption and to keep the water insoluble dioxins in solution. Plants were harvested 2, 7, 14, and 21 days after treatment, dissected into treated and untreated parts, and analyzed separately. Neither dioxin nor chlorophenol was translocated from the treated leaf. A rapid loss of the dichlorodioxin and dichlorophenol occurred from the leaf surface. This loss may have resulted from volatilization. Very little TCDD was lost from soybean leaves while a gradual loss (38% in 21 days) did occur from oat leaves. [Pg.110]

Generally, it is most likely that metal NPs are stabilized by the aggregates of the non-functionalized imidazolium ILs rather than by the isolated ions. In addition, the interaction between ILs and the metal NPs have been evidenced by X-ray photoelectron spectroscopy (XPS), small-angle X-ray scattering (SAXS), isotope labeling, and surface-enhanced Raman spectroscopy (SERS) techniques. [Pg.12]

The commercially available dicyanomethylene squaraine dye Seta-670-mono-NHS showed extremely low blinking effects and good photostability when used in single-molecule studies of multiple-fluorophore labeled antibodies [113]. Seta-670-mono-NHS and Seta-635-NH-mono-NHS were covalently labeled to antibodies and used in a surface-enhanced immunoassay [114]. From the fluorescence intensity and lifetime changes determined for a surface that had been coated with silver nanoparticles, both labeled compounds exhibited a 15- to 20-fold... [Pg.93]

A variation on the theme of conventional assay uses both lanthanide-labeled and biotin-labeled single strands to form split probes for sequence of target strands (Figure 12).120 When both of these bind to DNA, the complex binds (via the biotin residue) to a surface functionalized with streptavidin, immobilizing the europium and allowing assay to be carried out. This approach is already very sensitive to DNA sequence, since both sequences must match to permit immobilization of the lanthanide, but can be made even more sensitive by using PCR (the polymerase chain reaction) to enhance the concentration of DNA strands. In this way, initial concentrations corresponding to as few as four million molecules can be detected. This compares very favorably with radioimmunoassay detection limits. [Pg.931]

Deckert V., Zeisel D., Zenobi R., Vo-Dinh T., Near-field surface enhanced Raman imaging of dye-labeled DNA with 100-nm resolution, Anal. Chem. 1998 70 2646-2650. [Pg.254]

Advances have been achieved in recent years, such as the use of CL reagents as labels to derivatize and sensitively determine analytes containing amine, carboxyl, hydroxy, thiol, and other functional groups and their application in HPLC and CE [35, 36], the synthesis and application of new acridinium esters [37], the development of enhanced CL detection of horseradish peroxidase (HRP) labels [38], the use of immobilization techniques for developing CL-based sensors [39-42], some developments of luminol-based CL in relation to its application to time-resolved or solid-surface analysis [43], and the analytical application of electrogenerated CL (ECL) [44-47], among others. [Pg.59]


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See also in sourсe #XX -- [ Pg.406 ]




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Surface labeling

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