Elements: Molecules, microscope, lasers, fluorophores
For a long time, scientists were restricted by the range of view by a regular optical microscope. There was always a limit on how closely you can see an object under the scope. With the invention of fluorescent microscopy, it is now easier to view these particles by using fluorescence to illuminate the image. Developed by Stefan Hall, stimulated emission depletion (STED) microscopy is a technique that creates super-resolution images using fluorophores. It has been developed to bypass the diffraction limit of normal light microscopy. In optical microscopy, the limit is usually around 200 nanometers. This means that it can create high-resolution images at the nanoscale. This technique utilizes two lasers to “activate” the specimen. The first excites the flourophores using a green laser. Directly after, a second red beam (STED pulse) is used to deplete the “excited” molecules. This inhibits the outer regions of the image from illuminating and create an illuminated, tightly focused area, with very high resolution. This technology is currently the fastest nanoscopy method, with images of 60 to 80 nanometers in resolution at up to 80 frames per second.
These discoveries are important because with this new technology, scientists are able to study the smallest parts of life that couldn’t be seen before. It is mainly used in the fields of membrane research, cell biology, and neurobiology. With the work of this microscopy, cancerous cells and diseases can be be scoped using STED to light up the toxic cells and can be recognized and removed more easily, and more accurately. This allows us to study diseases and health problems at whole new level.