Maybe this is an excuse to show off these incredible images created with the Leica TCS SP8 MP, but why not take a look back at where this technology came from while we’re at it?
What we’re seeing here is a 3D image with optical sectioning using a multiphoton microscope. The phenomenon behind this technology is called two-photon absorption (TPA). Essentially, two photons are absorbed at the exact same time in order to excite a molecule from one state to a higher energy electronic state. Thinking back to high school chemistry, light is given off once that molecule decays back to a lower state.
Maria Goeppert-Mayer, the German-born American theoretical physicist, first predicted this process in her doctoral dissertation in 1931. It wasn’t until 30 years later, with the invention of the laser, that experimental verification for TPA was possible.
TPA was used as a spectroscopic tool until the 1980s. Once more developments in the field occurred, different applications were demonstrated. A few of them being photodynamic therapy, optical data storage, and imaging (obviously).
Watt W. Webb is best known for suggesting using TPA for imaging and microscopy. In 1990 he co-invented mulitphoton microscopy along with Winfried Denk and Jim Strickler. Earlier in his career, Webb pioneered techniques in fluorescent correlation spectroscopy (FCS). The combination of TPA and FCS resulted in high resolution, high signal-to-noise images.
One of the biggest advantages to multiphoton microscopes is the use of long wavelength, low energy excitation lasers. This is less damaging to live cells and introduces fewer toxic effects. This unique attribute is responsible for the in vivo microscopy you’re seeing in these images. Developments in medical endoscopy are being explored since the potential for in vivo, in situ real-time diagnostics is there.
This concludes our small lesson in multiphoton microscopes. Class dismissed.
This year’s big winner was video of a developing fruit fly embryo made from 30-second snippets pieced together from the first 24 hours of a fly’s life. The video is a fascinating view of cells multiplying and differentiating as the larva goes from a blob to a developed creature and begins to crawl away.
Check out the video below and check out all the top winners at Wired Magazine.
Every year Nikon holds a global competition to find the greatest work in photomicrography. Since 1975 they’ve encouraged professionals and enthusiasts alike to submit their work to show off the natural beauty that few ever see.
This year brought over 1200 entries from 79 countries around the world. Submissions featured everything from brine shrimp, jumping spider eyes and caterpillar legs to bovine pulmonary arteries, cricket tongues and the circuitry of a DVD reader. Each one shows a unique perspective of the world that can only be seen through microscopy. Check out the full gallery of 2014’s winners and honorable mentions at Nikon Small World
If you’re reading this, chances are you have more than a casual interest in the field. We at North Central Instruments encourage everyone to participate in the public submission. Not feeling up to the challenge? You’ve got plenty of time. The next deadline for submissions is April 30th 2015.
It’s time to jump in at start exploring the world that only microscopy gives us access to. For complete details on the Small World contest. Check out. http://www.nikonsmallworld.com/enter