The Development of Fluorescence Microscopy

The fluorescence microscope (wide-field, scanning, confocal, one-photon excitation, multiphoton excitation) is an extremely useful and ubiquitous instrument in biological and medical laboratories. The fluorescence microscope provides enhanced contrast, single protein specificity and single molecule sensitivity. Progress in the technical development over more than 100 years of instrument design and fluorescent probe synthesis has contributed to the continuing widespread utility of the fluorescence microscope. Modern advances in instrumentation include the use of continuous wave and pulsed laser light sources, dichroic filters, photomultipliers, avalanche photodetectors and charge-coupled device detectors. The invention of the two-photon excitation microscope provides for microscopic imaging of live cells and whole organisms. The development of specific dyes, physiological probes and molecular probes (intrinsic and extrinsic) stimulated the widespread use of fluorescence microscopy in the life sciences. Recently, genetically expressed fluorescent proteins and quantum dots provide new research capabilities for the intravital fluorescence microscope.