Excitation emission matrix spectroscopy

Coble, P.G. 1996. Characterization of marine and terrestrial DOM in seawater using excitation-emission matrix spectroscopy. Marine Chemistry, 51, 325-346. 

Time-Gated Excitation-Emission Matrix Spectroscopy... 

Figure 32.1 (a) A schematic illustration of time-gated excitation-emission matrix spectroscopy, (b) A typical example of the 3D fluorescence data measured for Rhodamine 590 in ethanol... 

Santfn, C., Y. Yamashita, X. Otero, M. Alvarez, and R. Jaffe. 2009. Characterizing humic substances from estuarine soils and sediments by excitation-emission matrix spectroscopy and parallel factor analysis. Biogeochemistry 96, no. 1 131-147. doi 10.1007/ S10533-009-9349-1. 

Jiang, F., Lee, F.S., Wang, X., and Dai, D. (2008). The application of excitation/emission matrix spectroscopy combined with multivariate analysis for the characterization and source identification of dissolved organic matter in seawater of Bohai Sea, China. Mar. Chem., 110,109-119. 

Bidimensional fluorescence spectra are commonly obtained in the three modes of emission, excitation, and synchronous-scan excitation, whereas tridimensional fluorescence (or total luminescence) spectra are obtained in the form of excitation-emission matrix (EEM) plots by measuring the fluorescence intensity emitted as a function of the wavelength over a range of excitation wavelengths. This technique allows to obtain more detailed information than that obtained by using conventional monodimensional fluorescence (Mobed et al., 1996). Fluorescence spectroscopy has provided valuable information on the molecular structure, functionalities, conformation, and intramolecular and intermolecular interactions of HS from organic amendments and unamended and amended soils (Senesi et al., 1990,1996, 2007 Mobed et al., 1996 Chen et al., 2003 Senesi and Plaza, 2007). 

Molecular fluorescence spectroscopy is a commonly employed analytical method that is sensitive to certain chemical properties of FA (9-13). Fulvic acid s molecular fluorescence is principally due to conjugated unsaturated segments and aromatic moieties present in the macromolecule (14). Several types of fluorescence spectra can be measured, including an excitation emission matrix or total luminescence spectrum, constant offset synchronous fluorescence, excitation spectra, and emission spectra, furnishing the researcher with useful data. The ability to resolve and select multiple fluorescent species makes these approaches extremely useful for studying FA relative to its chemical reactivity. 

Any analytical data obtained by hyphenated instruments or by two-way spectroscopic techniques such as excitation-emission fluorescence spectroscopy are bilinear ones. The bilinear data matrix has a very useful property, namely the rank of such matrix obtained with any chemical mixture is equal to the number of chemical components in the mixture. Thus, theoretically, the rank of a data matrix of any pure chemical component is unit. It can be expressed by the product of two vectors ... 

Y.G. Chung, J.A. Schwartz, C.M. Gardner, R. Sawya, S.L. Jaques (1994). Fluorescence of normal and cancerous brain tissue the excitation/emission matrix. In Robert R. Alfano (Ed.), Advances in Laser and Light Spectroscopy to Diagnose Cancer and other Diseases (SPIE Proc. Vol. 2135, pp. 66-75). 

Guimet, R, Boque, R., and Ferre, J. Application of unfold principal component analysis and parallel factor analysis to the exploratory analysis of olive oils by means of excitation-emission matrix fluorescence spectroscopy. Analytica Chimica Acta, 515, 75-85. 2004. 

Total luminescence spectroscopy (TLS) is the simultaneous measurement of excitation, emission and intensity wavelengths of compound fluorophores [140-142]. This technique is mainly used for large ceU numbers in aqueous suspensions. In TLS the distinct fluorescence data that is generated from a three-dimensional matrix or excitation-emission matrix (EEM) of a specific microorganism is used for identification. Compared to two-dimensional emission spectra, this technique is highly sensitive and selective [143]. 

Holbrook, R.D., DeRose, P.C., Leigh, S.D., Rukhin, A.L., and Heckert, N.A. (2006). Excitation-emission matrix fluorescence spectroscopy for natural organic matter characterization A quantitative evaluation of calibration and spectral correction procedures. Appl. Spectrosc., 60(7), 791-799. 

Figure 6.8. Example of the use of rank annihilation factor analysis for determining the concentration of tryptophane using fluorescence excitation-emission spectroscopy. In the top left plot the unknown sample is shown. It contains three different analytes. The standard sample (only tryptophane) is shown in the top right plot. In the lower right plot, it is shown that the smallest significant (third from top) singular value of the analyte-corrected unknown sample matrix reaches a clear minimum at the value 0.6. In the lower left plot the unknown sample is shown with 0.6 times the standard sample subtracted. It is evident that the contribution from the analyte is practically absent.

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