Journal of Biomedical Optics • Open AccessFluorescence Lifetime Spectroscopy and Imaging: Principles and Applications in Biomedical Diagnostics
The combination of spectroscopy and microscopy has provided the researcher and the clinician with a variety of optical devices that are both useful and prevalent in both the laboratory and the clinic. Typically, spectroscopic studies were based on intensity measurements. The absorption spectrum, emission spectrum, anisotropy, and the fluorescence lifetime were measured. Biophysicists and later cell biologists began to use fluorescent molecules to investigate the structure and the function of biological molecules such as antibodies and proteins. Later, more complex molecular assemblies such as cell membranes or the Golgi apparatus were investigated using fluorescence microscopy. Then these techniques were applied to tissues and organisms, and finally to in vivo human studies, such as the skin, the eye, and the heart.