Work

Advances in Fluorescence Spectroscopy: Multi-Photon Excitation, Engineered Proteins, Modulation Sensing and Microsecond Rhenium Metal-Ligand Complexes

Year: 1999

Type: article

Abstract: The technology and applications of fluorescence spectroscopy are rapidly advancing.In this overview presentation we summarize some recent developments from this laboratory.Two and three-photon excitation have been observed for a wide variety of intrinsic and extrinsic fluorophores, including tryptophan, tyrosine, DNA stains, membrane probes, and even alkanes.It has been possible to observe multi-photon excitation of biopolymers without obvious photochemical or photo-thermal effects.Although not described in our lecture, another area of increasing interest is the use of engineered proteins for chemical and clinical sensing.We show results for the glucose-galactose binding protein from E. coli.The labeled protein shows spectral changes in response to micromolar concentrations of glucose.This protein was used with a novel sensing method based on the modulated emission of the labeled proteins and a long lifetime reference fluorophore.And finally, we describe a recently developed rhenium complex which displays a lifetime near 3 µs in oxygenated aqueous solution.Such long life- time probes allow detection of microsecond dynamic processes, bypassing the usual nanosecond timescale limit of fluorescence.The result of these developments in protein engineering, sensing methods, and metal-ligand probe chemistry will be the increased use of fluorescence in clinical chemistry and point-of-care analyses.

Source: Acta Physica Polonica A

DOI: 10.12693/aphyspola.95.179