Multidimensional luminescence measurements

Abstract

Abstract : Luminescence spectroscopy has long been recognized as a tool for the quantitative and qualitative identification of a wide range of molecular systems. However, the resolving power of these techniques is often limited for similar compounds because absorption and emission peaks are typically broad banded and leads to overlapping spectra. To increase the resolving power of luminescence studies, recent studies have used multidimensional luminescence measurements (MLM) (use of two or more parameters of luminescence) to increase selectivity. Complex mixtures may be analyzed by rapidly acquiring fluorescence data as a function of multiple excitation and emission wavelengths. Advances in instrumentation and data reduction strategies allow the discrimination of mixtures in overlapping spectra by capitalizing on differences in fluorescence lifetime or fluorescence depolarization measurements. Fluorescence detected circular dichroism (FDCD) has been used to resolve optically active fluorescent compounds. Additionally, luminescence measurements may be combined with a range of measurements such as quenchometry and chromatography to yield very selective determinations.