microscopy – GOLLYGEE!

The Nobel prizes were awarded this week. Each year there are three science related awards in the fields of medicine, physics and chemistry.

In the field of medicine, the award went to John O´Keefe, May-Britt Moser and Edvard I. Moser for discovering the brain cells that make up our positioning system. In 1971 John O’Keefe discovered that when a rat was in a certain part of the room, one part of the hippocampus was always activated. When the rat was in other parts of a room there were different cells activated. He termed these cells “place cells” and determined that they formed a map. In 2005, the Mosers discovered what they called “grid cells”. These cells generated a coordinate system and aid in finding our way along paths. Read more about the physiology and medicine prize here.

This years physics medal went to the invention of LEDs and was awarded to Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura. The three researchers contributed to the development of LED technology, which is prevalent in today’s telephones, lamps, and computers. LED lights emit brighter light than incandescent lights and for longer periods of time. Read more about the award at Scientific American. The press release is here.

The chemistry prize was awarded to Eric Betzig, Stefan Hell, and William Moerner for developing super resolved fluorescence microscopy. Researchers thought they were limited by the limit of diffraction when it came to resolving images under a microscope. The three Nobel recipients have developed technology that helped overcome this limitation and resolve images into the nanometer scale. Stefan Hell developed a technique called stimulated emission depletion microscopy or STED. Bezig and Moerner, working separately, performed the groundwork for the development of single molecule microscopy. You can read the press release here, and a more detailed description of high resolution microscopy here.

Another use for graphene. Like I said in the last post, graphene is a wonderous material. Today’s magical graphene finding is that it can be used in microscopy to investigate molecules on the atomic level. From Scientific American:

A liquid graphene bubble lets researchers view molecules inside at the atomic level. Image from Scientific American. Image courtesy of Alivisatos, Lee and Zettl research groups, Lawrence Berkeley National Laboratory and KAIST

In the April 6 issue of Science, a team from Lawrence Berkeley National Laboratory, the University of California, Berkeley, and the Korea Advanced Institute of Science and Technology in Daejeon, South Korea, reports that liquids fare just fine inside the vacuum of an electron microscope when encapsulated in graphene. The researchers sandwiched nanoscale pockets of liquid between two sheets of graphene and then used a transmission electron microscope to peer inside.

They found that the graphene capsules shielded the fluid from vacuum while also allowing for atomic-resolution imaging, which had been a challenge for other liquid capsules fashioned from materials such as silicon nitride. “The problem with that is the silicon nitride is already 25 nanometers thick. It’s a lot thicker than graphene,” says Jungwon Park, a U.C. Berkeley graduate student and a co-author of the new study. “It scatters a lot of the electron beam out, and it reduces the resolution and contrast a lot.”

The walls of the graphene liquid capsule, on the other hand, are so slim—less than a nanometer thick—that the researchers could resolve individual platinum atoms inside.

More here [Scientific American] and here [Science, abstract available].

GOLLYGEE!

Tag: microscopy

2014 nobel prizes

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