Luminescence spectrometry

Winefordner, J. D., Schulman, S. G., O Haver, T. C. Luminescence Spectrometry in Analytical Chemistry, Wiley-Interseience, London 1972. 

The active state of luminescence spectrometry today may be judged ly an examination of the 1988 issue of Fundamental Reviews of Analytical Chemistry (78), which divides its report titled Molecular Fluorescence, Phosphorescence, and Chemiluminescence Spectrometry into about 27 specialized topical areas, depending on how you choose to count all the subdivisions. This profusion of luminescence topics in Fundamental Reviews is just the tip of the iceberg, because it omits all publications not primarily concerned with analytical applications. Fundamental Reviews does, however, represent a good cross-section of the available techniques because nearly every method for using luminescence in scientific studies eventually finds a use in some form of chemical analysis. Since it would be impossible to mention here all of the current important applications and developments in the entire universe of luminescence, this report continues with a look at progress in a few current areas that seem significant to the author for their potential impact on future work. 

St John PA, McCarthy WJ, Winefordner JD (1966) Application of signal-to-noise theory in molecular luminescence spectrometry. Anal Chem 38 1828... 

A Fernandez-Gutierrez, A Munoz de la Pena. In SG Schulman, ed. Molecular Luminescence Spectrometry. Methods and Applications Part I. Vol 77. New York Wiley, 1985, p 372. 

Special issues of the International Symposia on Quantitative Luminescence Spectrometry in Biomedical Sciences. Anal Chim Acta 290 1-248, 1994 and Anal Chim Acta 303 1-148, 1995. 

Vol. 34. Neutron Activation Analysis. By D. De Soete, R. Gijbels, and J. Hoste Vol. 35 Laser Raman Spectroscopy. By Marvin C. Tobin Vol. 36 Emission Spectrochemical Analysis. By Morris Slavin Vol. 37 Analytical Chemistry of Phosphorus Compounds. Edited by M. Halmann Vol. 38 Luminescence Spectrometry in Analytical Chemistry. By J. D.Winefordner, S. G. Schulman, and T. C. O Haver... 

Considerably more work is required before these techniques can he introduced in court, hut our studies and the work of others show that photoluminescence techniques have potential for wide application in forensic science. Indeed, because of the significant advances demonstrated in recent years, one can expect to see spectrophotofluorometers become as commonplace as infrared spectrometers in a crime laboratory. Although luminescence spectrometry is not, in general, as specific as infrared spectrometry, it is considerably more sensitive and convenient. 

It has long been recognized that both the diffuse spectra and quenching problems can be alleviated by performing the fluorescence measurement in a low-temperature solid matrix, rather than in a fluid solution. The most common low-temperature matrices used in molecular fluorometric analysis are frozen liquid solutions the analytical characteristics of frozen-solution luminescence spectrometry have been discussed extensively in the literature (2-10). Obviously, MI represents an alternative technique to use of frozen liquid solutions for low-temperature fluorometric analysis. There are two principal advantages of MI over frozen-solution fluorometry. First, in MI, any material which has an appreciable vapor pressure at room temperature can be used as a matrix one is not limited by the... 

Incandescent lamps are not sufficiently intense to be useful in luminescence spectrometry, although their stability cannot be matched by gas discharge and arc lamps. 

A number of less commonly used analytical techniques are available for determining PAHs. These include synchronous luminescence spectroscopy (SLS), resonant (R)/nonresonant (NR)-synchronous scan luminescence (SSL) spectrometry, room temperature phosphorescence (RTP), ultraviolet-resonance Raman spectroscopy (UV-RRS), x-ray excited optical luminescence spectroscopy (XEOL), laser-induced molecular fluorescence (LIMP), supersonic jet/laser induced fluorescence (SSJ/LIF), low- temperature fluorescence spectroscopy (LTFS), high-resolution low-temperature spectrofluorometry, low-temperature molecular luminescence spectrometry (LT-MLS), and supersonic jet spectroscopy/capillary supercritical fluid chromatography (SJS/SFC) Asher 1984 Garrigues and Ewald 1987 Goates et al. 1989 Jones et al. 1988 Lai et al. 1990 Lamotte et al. 1985 Lin et al. 1991 Popl et al. 1975 Richardson and Ando 1977 Saber et al. 1991 Vo-Dinh et al. 1984 Vo- Dinh and Abbott 1984 Vo-Dinh 1981 Woo et al. 1980). More recent methods for the determination of PAHs in environmental samples include GC-MS with stable isotope dilution calibration (Bushby et al. 1993), capillary electrophoresis with UV-laser excited fluorescence detection (Nie et al. 1993), and laser desorption laser photoionization time-of-flight mass spectrometry of direct determination of PAH in solid waste matrices (Dale et al. 1993). 

Low temperature-molecular luminescence spectrometry (LT-MLS), SLS, and HPLC/fluorescence detection have been used to measure pyrene in broiled hamburger (Jones et al. 1988). A comparison of the three methods showed that sensitivity for all three methods was in the low-ppb range and that all methods were comparably reproducible (6-9% RSD). Adequate recovery (75-85%) was obtained from the extraction procedure for all three methods. While HPLC is the least expensive and easiest to operate, it has the longest analysis time (30 minutes), and it provides the least resolution of components. LT-MLS is the fastest technique (5 minutes), and it gives mores spectral information than the other two methods. SLS, with an analysis time of 15 minutes, offers no real advantages over LT-MLS other than cost of equipment. 

Jones BT, Glick MR. Mignardi MA. et al. 1988. Determination of polycyclic aromatic hydrocarbons in cooked beef by low-temperature molecular luminescence spectrometry using a moving sample cooling belt. Appl Spectrosc 42(5) 850-853. 

In the past, molecular luminescence spectrometry was always conducted with single channel systems involving a photomultiplier tube (PMT) as the detector. The availability of multichannel detectors with internal gain has provided a new powerful tool for luminescence measurements, and several types of applications have been reported (1-15). This paper is concerned with the application of an intensified diode array dynamic molecular fluorescence and chemiluminescence measurements. In this paper the types of measurements and analytical systems for which multichannel detectors are used in our laboratory are introduced. Next the specific IDA system used is presented along with important hardware and software considerations. Third, the characteristics of the IDA detector are reviewed to give some perspective about its influence on the quality of measurements. Finally, some typical applications to chemical systems are presented to illustrate the advantages of multichannel detection. 

JD Winefordner, SG Schulman, TC O Haver. Luminescence Spectrometry in Analytical Chemistry. New York Wiley Interscience, 1972. 

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