Holographic fluorescence imaging to 3-D track extracellular vesicles

Biologists commonly use fluorescence microscopy due to the molecular specificity and super-resolution of the technique. However, the method is withheld by imaging limits. In a new report on Science Advances, Matz Liebel and a research team at the Barcelona Institute of Science and Technology and the Massachusetts General Hospital in Spain and the U.S. reported an imaging approach to recover the full electric field of fluorescent light using single-molecule sensitivity. The team experimented with the concept of digital holography for fast fluorescence detection by tracking the three-dimensional (3-D) trajectory of individual nanoparticles using an in-plane resolution of 15 nanometers. As proof-of-concept biological applications, the researchers imaged the 3-D motion of extracellular vesicles inside live cells.