In laser induced fluorescence (LIF), a sample absorbs electromagnetic radiation from a laser and some of its molecules are excited to higher energy levels. Fluorescence is emitted at wavelengths longer than the exciting radiation. Both the absorbed and emitted wavelengths are characteristic of a given molecule. Because the emitted wavelength is different than the exciting wavelength, fluorescence detection is very sensitive relative to absorption measurements. In some cases LIF sensitivities approach the detection of a single atom or molecule.

In the biological arena, LIF is used for early cancer detection, to study atherogenesis, and to track gene expression. Fluorescent probes (fluorophores) are finely tuned to bind to specific proteins, viruses, enzymes, and other target entities. By using probes with different emission spectra such as coumarin (blue fluorescence), fluorescein (green), and rhodamine (orange-red), multiple parameters can be examined in a single experiment. Scientists are able to access very exciting information through fluorescence microscopy imaging. That is, they can monitor processes happening in a living cell. Much will be learned about the connection of genetic defects and hereditary diseases and proteomics or the actions of proteins in a cell.

Physical chemists employ LIF in studies of the electronic structure of molecules. Environmental applications include monitoring concentrations of gases in the atmosphere, flames, and plasmas, and remote sensing using light detection and ranging (LIDAR). LIF based handheld instruments screen for surface uranium contamination. LIF is used for airborne hyperspectral imaging to monitor vegetation status and water pollutants. LIF spectroscopy is a nondestructive analytical tool for artwork diagnostics as each pigment gives a distinct spectral signature and the signatures of a suspect work can be compared to those of authenticated pieces. LIF offers very sensitive detection for the separation techniques capillary electrophoresis (CE) and microbore high performance liquid chromatography (HPLC).

Laser Science, Inc. offers nitrogen lasers, tunable dye lasers, and tunable UV lasers giving the researcher the capability of inexpensively selecting the ideal exciting frequency from a broad range of laser frequencies. The pulsed nature of the lasers enables them to deliver high peak power without damaging the sample. Lasers can be focussed to a fine point for fluorescence studies of small samples. For more information, please contact us by phone at (508) 553-2390, fax at (508) 553-2355, or use the Contact Us form.

Laser Science, Inc.
8E Forge Parkway
Franklin, MA 02038

Phone: 508-553-2353
Fax: 508-553-2355