White light excitation fluorescence (WLEF) : Part II. Analysis of complex multifluorophoric systems

Abstract

The scope of white light excitation fluorescence in analyzing multifluorophoric systems has been explored. White light excitation fluorescence (WLEF) spectra retain the resultant fluorescence signature of all the fluorophores and their interactions although, in contrast to excitation-emission-matrix fluorescence (EEMF) spectra, resolution along the excitation axis is lost. The demonstration of the advantages of WLEF with regard to fiber optic compatibility, sensitivity, selectivity and simultaneous detection of multiple fluorophores suggests that WLEF based analytical techniques can be methods of choice in certain cases, especially with regard to low cost in situ analysis of an analyte. The analysis of multifluorophoric systems by WLEF using a fiber optic fluorimeter clearly shows the effectiveness of WLEF (i) in two-fluorophoric systems at low fluorophore concentrations in which the spectral additivity is retained and (ii) in a complex multifluorophoric system like diesel-kerosene mixtures.