Molecular Fluorescence Excitation-Emission Matrices Relevant to Tissue Spectroscopy¶

Abstract

In vivo and ex vivo studies of fluorescence from endogenous and exogenous molecules in tissues and cells are common for applications such as detection or characterization of early disease. A systematic determination of the excitation–emission matrices (EEM) of known and putative endogenous fluorophores and a number of exogenous fluorescent photodynamic therapy drugs has been performed in solution. The excitation wavelength range was 250–520 nm, with fluorescence emission spectra collected in the range 260–750 nm. In addition, EEM of intact normal and adenomatous human colon tissues are presented as an example of the relationship to the EEM of constituent fluorophores and illustrating the effects of tissue chromophore absorption. As a means to make this large quantity of spectral data generally available, an interactive database has been developed. This currently includes EEM and also absorption spectra of 35 different endogenous and exogenous fluorophores and chromophores and six photosensitizing agents. It is intended to maintain and extend this database in the public domain, accessible through the Photochemistry and Photobiology website (http://www.aspjournal.com).

Laser‐induced autofluorescence spectral ratio reference standard for early discrimination of oral cancer

“…Many research groups have reported the autofluorescence around 500 nm as an emission from endogenous fluorophores, like NADH, FAD, collagen, elastin, and amino acids, and emissions at 635 and 705 nm from enhanced PpIX presence in malignant tissues 4–6, 10–12, 23, 24. In addition to these peaks, we noticed a prominent peak around 685 nm in malignant tissues that appears between the PpIX peaks.…”

Optical and X‐ray Fluorescence Spectroscopy Studies of Bone and Teeth in Newborn Rats After Maternal Treatment with Indinavir

“…Lipids with emission in the 450–660 nm range take part in the calcification process while vitamin D with maximum emission at 480 nm is thought to be a bone‐regulating factor. Moreover, molecular fluorescence excitation–emission matrix relevant to tissue spectroscopy (33) contributes emission from collagen I (predominant in bone) at the end of the short wavelength range taken into consideration in this work. This is essential because collagen makes up approximately 90% of the organic matrix in bone.…”

Review of Neurosurgical Fluorescence Imaging Methodologies

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