Scientists can now attain superior-resolution microscopy by means of a technique called stimulated emission depletion (STED) microscopy. This advanced imaging system has considerably surpassed previous limitations associated with the performance of microscopes, allowing imaging of objects tinier than the light’s wavelength that is being utilized for examining them.
This excellent vision capability was made possible by employing a fluorescent dye of a single color which is capable of absorbing and releasing energy, showing the cells and its components, for example proteins, in fine details.
Present usage of STED microscopy is confined to allow multi-color imaging in protected or fixed cells and single color imaging in living cells. However, in order to examine active procedures that include protein interactions, the need for a dual-color imaging approach is important to perform research in living cells. A research team from Yale University has successfully implemented dual-color imaging and the result was published in the latest issue of the journal, Biomedical Optics Express, by the Optical Society's (OSA). The reason for their success lay in dealing with the difficulties associated with the labeling of living cells’ proteins using dyes ideal for dual-color imaging. By introducing fusion proteins, targeting between the dye and protein is enhanced and the gap is efficiently bridged. This enabled the research team to obtain resolutions of about 82 nm and 78 nm for epidermal growth factor receptor and epidermal growth factor on performing 22 continuous dual-color scans for two proteins in live cells.
The researchers anticipate that application of this technique and various other novel techniques will enable to advance STED microscopy for live cell to three or more colors, thereby allowing three-dimensional imaging.