Luminescence instrumentation

Definition and Uses of Standards. In the context of this paper, the term "standard" denotes a well-characterized material for which a physical parameter or concentration of chemical constituent has been determined with a known precision and accuracy. These standards can be used to check or determine (a) instrumental parameters such as wavelength accuracy, detection-system spectral responsivity, and stability (b) the instrument response to specific fluorescent species and (c) the accuracy of measurements made by specific Instruments or measurement procedures (assess whether the analytical measurement process is in statistical control and whether it exhibits bias). Once the luminescence instrumentation has been calibrated, it can be used to measure the luminescence characteristics of chemical systems, including corrected excitation and emission spectra, quantum yields, decay times, emission anisotropies, energy transfer, and, with appropriate standards, the concentrations of chemical constituents in complex S2unples. 

Perkin-Elmer and Hamilton both supply luminescence instruments (see Appendix 1). 

Luminescence instrument LS-3B luminescence instrument LS-5B Accessories low flow cell, cell holders, bioluminescence spectroscopy, fluorescence spectro scopy, recorder/printers, low-temperature luminescence, fluorescence plate reader, polarization accessory, microfilm fluorimeter LS-2B... 

If the researcher has commercial molecular luminescence instrumentation (e.g., a spectrofluorometer) available, then solid-state luminescence data should not be difficult to obtain. Many good references are available discussing the basic theory of luminescence, " so the focus herein will be on its use in solid-state applications. Instrumentation normally consists of an excitation source, excitation wavelength selector, sample compartment, emission wavelength selector, and detector. The largest issue for conducting measurements on... 

J. R. Lakowicz, Principles of Flnorescence Spectroscopy , Springer, New York, 2006, Considered by many the seminal reference material on luminescence instrumentation and basic measurements, although solid-state measurements are not directly addressed. 

The basic components of luminescence instrumentation are generally arranged as shown in Fig. 1. The sample is placed in a sample cell and excited by either ultraviolet or visible light from a source. A filter or monochromator may select a particular excitation... 

We were fortunate to have oral and poster presentations given by scientists from 19 countries, as well as active participation from industrial exhibitors. The sessions included luciferase-based bioluminescence, photoprotein-based bioluminescence, fundamental aspects and applications of chemiluminescence, luminescence imaging, fluorescence quantum dots and other inorganic fluorescent materials, phosphorescence and ultraweak luminescence, instrumentation and new methods. 

Some luminescence instruments allow simultane-ously scanning both the excitation and the emission wavelengths with a sntall w avelength difference between them. The spectrum that results is known as a synchronous spectrum. A luminescence signal Is ob-... 

T he luminescence instruments shown in I igures 15-10 and 15-11 both monitor the source intensity via a ret-crence photomultiplier. Most commonly, the ratio of the sample luminescence signal lo the signal from the reference detector is continuously obtained. This can compensate for source intensity fluctuations and drift. Both doubic-bcam-in space and doiihlc beam-in time designs are employed. 

Modern computer-based luminescence instruments have many different data-manipulation schemes available in software. Common data-manipulation and display options include blank signal subtraction, production of corrected excitation and emission spectra, calculation and display of difference and derivative... 

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