Scientists have designed a new type of microscope that can see inside cells in real time. It’s called a light-sheet microscope and uses 2D optical lattices to make sheets of light. Light-sheet microscopes have major advantages over traditional microscopes that use a single beam of light. The beam of light in traditional microscopes can heat up and damage samples, especially when used to image in 3D. This is because the only way to image in 3D with a microscope is to take serial images through subsequent planes of a sample, and stack these images together to make one 3D image. This isn’t a problem if samples are fixed and stained. But it is a problem if samples are still alive, especially if you want to image them several times over hours, days or weeks.
Light-sheet microscopes have been used before now to image things cell-size or bigger. But up until last week they haven’t been able to capture what is happening inside a cell because the sheets of light were too thick. A paper published last week used ultra-thin sheets of light that were only 250 nanometres wide in a microscope that could record up to 1000 frames per second. In this set-up the blue-green light sheet scanned through objects at a rate of hundreds of planes per second to build up a 3D image from inside cells. The light sheet was so thin that it did not bleach or otherwise damage the samples. It also didn’t cause much background light interference with the image – another problem that is common with traditional microscopes.
Several teams of scientists used this new technology to image different biological processes from transcription factor proteins binding to DNA right up to worm and fly embryos developing.
This is really amazing because up until now we have had to infer what is happening inside cells from static images and experiments done on isolated proteins and DNA etc. Now we can sit back and watch what is happening in real time. This will really revolutionise how experiments are done.
This technology was invented by scientists at the Howard Hughes Medical Institute. They have licensed it to Carl Zeiss in Germany and Intelligent Imaging Innovations in Denver. So we should see these microscopes for sale soon.
The Scientific Paper: