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Instrumentation fluorescence

Fluorometers designed for research purposes(31) are typically equipped with a xenon arc lamp, monochromators, one or more photomultiplier tubes, cuvet holders, and a computer interface. Some research level fluorometers, such as the Perkin-Elmer LS50, have optional microtiter plate reading accessories with fiber optic bundles. This is convenient since 96-well microtiter plates are commonly used for immunoassay development, and many commercial immunoassays are based on the use of microtiter plates. Fluorometers designed for commercial immunoassay purposes are generally dedicated instruments with few, if any, data acquisition and reduction parameters that can be manipulated by the user. [Pg.456]


Hard et al (reference 110, 125, and submitted to/. Geophys, Res. 1991) have developed a system for the chemical conversion of HO2 to HO via the reaction HO2 + NO —> HO -I- N02. The hydroxyl radical is then measured by their low-pressure laser-induced-fluorescence instrument. Their multi-sample-channel LIF PAGE system is thus capable of simultaneous measurements of [HO ] (directly) and [H02 ] (by conversion to HO ). [Pg.86]

Williams-Thorpe, O., Potts, P. J., and Webb, P. C. (1999). Field-portable non-destructive analysis of lithic archaeological samples by X-ray fluorescence instrumentation using a mercury iodide detector Comparison with wavelength-dispersive XRF and a case study in British stone axe provenancing. Journal of Archaeological Science 26 215-237. [Pg.388]

A wide variety of X-ray fluorescence spectrometers may be used, depending on the nature and complexity of the sample, and on the number of samples to be analysed. To prove this and to indicate the substantial influence which the sample has on the choice of measuring instrument, let us consider some of the main characteristics of some X-ray fluorescence instruments used today [38]. These are shown in Table 14.11. [Pg.451]

Fluorescence Instrumentation and Measurements. Fluorescence spectra of the FS samples were obtained on a steady state spectrofluorometer of modular construction with a 1000 W xenon arc lamp and tandem quarter meter excitation monochromator and quarter meter analysis monochromator. The diffraction gratings In the excitation monochromators have blaze angles that allow maximum light transmission at a wavelength of 240 nm. Uncorrected spectra were taken under front-face Illumination with exciting light at 260 nm. Monomer fluorescence was measured at 280 nm and exclmer fluorescence was measured at 330 nm, where there Is no overlap of exclmer and monomer bands. [Pg.101]

Draw a diagram of a fluorescence instrument and point out the differences between it and the basic single-beam absorption spectrophotometer. [Pg.238]

What are the advantages and disadvantages to using an analyzer crystal in an x-ray fluorescence instrument, as depicted in Figure 10.7 ... [Pg.294]

FIAs can be based on steady-state intensity measurements without probe amplification, owing to the sensitivity of detection that is possible with fluorescence instrumentation, which exceeds that of spectrophotometers by two or three orders of magnitude. A sensitive fluorometer has been described for an estradiol assay(36) in which the limit of estradiol detection is 3 x KT11 M. Estradiol antibody labeled with rhodamine B is reacted with estradiol samples. Unreacted labeled antibody is removed with Sepharose-estradiol-casein beads, and the remaining fluorescence is directly proportional to the analyte concentration. The detection limit of rhodamine B on the same fluorometer is 5 x 1(T12 M. This instrument uses a 0.75 mW green helium-neon (HeNe) laser to irradiate the sample from above, at the air-liquid interface, to increase the light path and to decrease surface reflections. The sample compartment has a top-mounted photon trap, and a mirror mounted on the side of the sample compartment opposite the PMT to enhance detection. [Pg.460]

In addition to fluorescence intensity and polarization, fluorescence spectroscopy also includes measurement of the lifetime of the excited state. Recent improvements in the design of fluorescence instrumentation for measuring fluorescence lifetime have permitted additional applications of fluorescence techniques to immunoassays. Fluorescence lifetime measurement can be performed by either phase-resolved or time-resolved fluorescence spectroscopy. [Pg.285]

In the past ten years, numerous applications of fluorescence methods for monitoring homogeneous and heterogeneous immunoassays have been reported. Advances in the design of fluorescent labels have prompted the development of various fluorescent immunoassay schemes such as the substrate-labeled fluorescent immunoassay and the fluorescence excitation transfer immunoassay. As sophisticated fluorescence instrumentation for lifetime measurement became available, the phase-resolved and time-resolved fluorescent immunoassays have also developed. With the current emphasis on satellite and physician s office testing, future innovations in fluorescence immunoassay development will be expected to center on the simplification of assay protocol and the development of solid-state miniaturized fluorescence readers for on-site testing. [Pg.286]

There are four main types of fluorescence instruments, each providing distinctly different information ... [Pg.194]

The instrumental conditions for the hydride generation atomic fluorescence instrument are given in Table B.2. A diagram of the instrumental set-up is shown in Fig. B.l. [Pg.174]

Inject the standard into the sample loop of the HPLC instrument and observe the output of the atomic fluorescence instrument on the chromatographic integrator. On elution of the first arsenic species, switch the mobile phase from 0.0001 M K2SO4 to 0.1 M K2SO4 (step gradient elution). [Pg.175]

Two categories of fluorescence instruments are available from manufacturers ... [Pg.228]

Instruments used for the continuous monitoring of industrial production constitute the third category of X-ray fluorescence instruments. In most of these cases, the object is to measure a single element present in a fabrication process. [Pg.247]

X-ray fluorescence can be used to analyse all types of samples. Its applications are numerous, whether in research and development or in quality control of production. Initially, X-ray fluorescence was used in industries that treat metals of primary fusion or alloys and, more generally, in the mineral industry (for use one ceramics, cements, steel, glass, etc.). Because of the ease of use of common X-ray fluorescence instruments, its scope of application has expanded into other areas the photographic industry and semi-conductors (for impurity control in silicon chips), the petroleum industry, geology, paper mills, gas analyses (such as nitrogen), toxicology and environmental applications (dust, fumes from combustion, heavy metals, and dangerous materials in waste such as Pb, As, Cr, Cd, etc.). [Pg.249]

For sensors that are truly mass sensitive and for which the mass flow of sample through the sensing element is held constant as a function of pressure (for example, by use of electronic mass-flow controllers), instrument response is proportional to the mixing ratio independent of the pressure. For concentration-sensitive detectors, such as simple spectrophotometric instruments measuring absorbance or fluorescence, instrument response is a function of the absolute concentration, and the response will decrease for a constant mixing ratio as the pressure decreases. For example, the response of a pulsed fluorescence SO instrument sampling air containing a fixed... [Pg.115]

To assess the provenance of majolica pottery found in the Canary Islands, a sample of 55 sherds was obtained from two sites on Gran Canaria Island La Cueva Pintada (G ldar) and El Antiguo Convento de San Francisco (Las Palmas de Gran Canaria). The pottery was studied by X-ray fluorescence, instrumental neutron activation analysis, and X-ray diffraction. The results show one group that matches a reference group from Seville, an assessment that supports the historical record. However, the data also reveal samples whose provenance corresponds to other production centers on the Iberian Peninsula, such as Manises, Barcelona, and, possibly, an unknown Portuguese center. Moreover, it is possible that Italian and Dutch pottery have been identified thereby providing a complexity factor to the historical accounts. [Pg.376]

Further intercomparison studies are planned with the Hg translation based instrument with a pulsed fluorescence instrument and a filter collection based procedure in the near future. [Pg.398]

Figure 1. Schematic of laser-induced fluorescence instrumentation... Figure 1. Schematic of laser-induced fluorescence instrumentation...
Absorption and Fluorescence Instrumentation. Absorption spectra were obtained using a Princeton Applied Research Corp. (PARC) Model 1208 polychromator, a Perkin-Elmer 8 yL absorption flow-cell and a 50 watt deuterium light source. Fluorescence spectra were obtained using a Farrand Mark 1 Spectrofluorometer (previously described (13)) and either a 10 iiL Farrand micro flow-cell, or a Precision Cells, Inc. (Model No. 8830) 20 yL flow-cell. A PARC Model 1254 SIT detector, having a UV scintillator, was mounted on both the absorption polychromator and fluorescence spectrofluorometer. Spectral coverage in the absorption and fluorescence modes was 60 and 115 nm, respectively. All absorption and fluorescence spectra were obtained in one second, i.e., 32 scans of the SIT target. [Pg.116]

X-ray fluorescence analysis had been used for composition studies of various materials. Probably among the most important applications are research on metals and on inorganic pigments. Analyses similar to the ones I quoted are very helpful in authenticity studies and can aid the cosmetic industry, metallurgy, and so on. The demands archaeological chemistry made (nondestructiveness, small sample size, quick analysis, sensitivity) has helped significantly to develop x-ray fluorescence instrumentation. [Pg.6]

Middendorf, L.R., et al. (1998) Near-infrared fluorescence instrumentation for DNA analysis, in Near-Infrared Dyes for High Technology Applications, S. Daehne, Editor. 1998, Kluwer Academic Publishers, pp. 21-54. [Pg.133]

The constant Rq is dependent on several parameters 1) the relative orientation of the transition dipole moments of the two molecules (these dipoles are the spectroscopic transition dipoles), 2) the extent that the fluorescence spectrum of the donor overlaps with the absorption spectrum of the acceptor, and 3) the surrounding index of refraction. We will deal with each of these below (see Equation 8). Because many proteins have diameters less than lOnm, this distance dependence explains the usefulness of ERET for determiiung distances inside proteins as well as between interacting proteins, which is the reason that the name spectroscopic ruler was coined for FRET (20). ERET is a convenient method for determining the distance between two locations on proteins, or for determining whether two proteins interact intimately with each other. Fluorescence instrumentation is available in many laboratories, and a plethora of dyes and a wide variety of fluorescent proteins are now readily available. Therefore, FRET is a viable option for most researchers. With care, FRET can yield valuable information concerning protein-protein interactions, interactions of proteins with other molecules, and protein conformational changes. [Pg.513]

Kirby, E. P. Fluorescence instrumentation and methodology. In Excited States of Proteins and Nucleic Acids. Steiner, R. F., Weinryb, I. (Eds.) p. 31, New York Plenum 1971 Kirkov-Kaminska, E., Rothiewicz, K., Gradbowska, A Qiem, Phys. Letts. 58, 379 (1978) Kldpffer, W. J- Chem. Phys. 50, 2337 (1969)... [Pg.164]


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Dispersive instruments, atomic fluorescence

Fluorescence filter instruments

Fluorescence instrumentation electronics

Fluorescence measurements instrumentation

Fluorescence microscopy instrumentation

Fluorescence spectrometry instrumentation

Fluorescence spectrophotometry instrumentation

Fluorescence spectroscopy instrumentation

Fluorescent detection, instrument

Fluorescent detection, instrument detector

Fluorescent detection, instrument excitation source

Fluorescent detection, instrument laser

Fluorescent detection, instrument optical filter

Fluorescent detection, instrument photodiode

Fluorescent detection, instrument photomultiplier tube

Fluorescent optical sensors instrumentation

HPLC instrumentation fluorescence detectors

Instrumentation atomic fluorescence spectrometry

Instrumentation fluorescence decay

Instrumentation for Fluorescence and Phosphorescence

Instrumentation for fluorescence

Instrumentation single molecule fluorescence

Instruments cold-vapor atomic fluorescence

Instruments fluorescence

Instruments fluorescence

Instruments fluorescence spectroscopy

Time-resolved fluorescence instrumentation

Ultraviolet-visible fluorescence instrumentation

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