New Microscope Enables Real-Time 3-D Movies of Developing Embryos [Slide Show]: Scientific American

New Microscope Enables Real-Time 3-D Movies of Developing Embryos [Slide Show]: Scientific American: The researchers began by turning microscopy on its side—literally. In traditional fluorescence microscopy the whole sample is usually lit by the laser from above. A cameralike detector focuses on successive planes through the sample, snapping pictures from top to bottom that can be stacked into a 3-D picture. But throughout this process the full force of the laser blasts even cells whose light is not in focus for the detector. What the EMBL team realized was that if they swung the laser 90 degrees, so it shined through the sample from the side instead of from above, they could illuminate just the single slice on which the camera was focusing. None of the other cells were hit.

Suddenly, scientists could make movies that lasted for days. The cells under their microscopes, hit with only one five-thousandth of the energy used in traditional fluorescence microscopy, kept on dividing. The EMBL team took a record 24-hour-long movie of a developing zebra fish embryo.