An international collaboration led by the University Medical Center Göttingen (UMG), Germany, has developed a labeling method that distinguishes fluorescent labels not by color but by how long it takes a dye to emit fluorescence. This makes it possible to visualize eight different proteins in a cell simultaneously in a single step using standard microscopes. The results have been published in the journal ACS Nano.
Fluorescence microscopy is an important method in biomedical research that allows researchers to visualize specific proteins and cellular structures. Researchers typically use antibodies carrying fluorescent dyes to mark the proteins they want to study. When excited, the dyes fluoresce, and a microscope detects the light they emit. The problem: Conventional microscopes can detect only three or four colors at a time—for example, blue/purple, green, yellow/orange and red—so only that many proteins can be distinguished simultaneously.
An international research team led by Dr. Felipe Opazo, a research group leader at the Department of Neuro-and Sensory Physiology and the Center for Biostructural Imaging of Neurodegeneration (BIN) at the University Medical Center Göttingen (UMG), together with Dr. Roman Tsukanov, a postdoctoral researcher at the Third Institute of Physics at the University of Göttingen, has now opened up a second dimension. Alongside color, the researchers use a property rarely exploited until now: fluorescence lifetime, the few billionths of a second a dye glows after being excited by laser light.
