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An electron microscope that won't destroy living cells

An electron microscope that won't destroy living cells
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We’ve all seen those scary images of monstrous looking insects captured by high-resolution electron microscopes, like the house dust mite in the image above. One thing you may not be aware of though, is that all the creepy crawlies in such images are dead. That’s because the particle beam of electrons used to illuminate a specimen also destroys the samples, meaning that electron microscopes can’t be used to image living cells. Electrical engineers at Massachusetts Institute of Technology (MIT) have proposed a new scheme that can overcome this critical limitation by using a quantum mechanical measurement technique that allows electrons to sense objects remotely without ever hitting the imaged objects, thus avoiding damage.

Traditional electron microscopes use a particle beam of electrons, instead of light, to image specimens, which offers extremely high resolution – up to 0.2 to 10 nanometers – that's 10 to 10,000 times greater than a traditional microscope. With the new quantum microscope proposed by the MIT researchers, the electrons would not directly strike the object being imaged, but would instead flow around one or two rings, arranged one above the other.

These rings would be close enough together that the electron could hop easily between them, however, if an object (such as a cell) were placed between the rings, it would prevent the electron from hopping, and the electron would be trapped in one ring. This setup would scan one "pixel" of the specimen at a time, putting them all together to create the full image. Whenever the electron is trapped, the system would know that there is a dark pixel in that spot.

Assistant Professor Mehmet Fatih Yanik, senior author of the paper, says he expects the work "will likely ignite experimental efforts around the world for its realization, with perhaps the first prototype appearing in five years or so."

Before then technical challenges will need to be overcome, such as preventing the charged electron from interacting with other metals in the microscope. But Yanik believes that eventually such a microscope could achieve single-nanometer resolution, which would allow scientists to view molecules such as enzymes and nucleic acids inside living cells.

A non-invasive electron microscope could shed light on fundamental questions about life and matter, allowing researchers to observe molecules inside a living cell without disturbing them. If successful, such microscopes would surmount what Nobel laureate Dennis Gabor concluded in 1956 was the fundamental limitation of electron microscopy: "The destruction of the object by the exploring agent."

The MIT team’s research is detailed in the paper, "Non-destructive Electron Microscopy and Interaction-free Quantum Measurements,” which appears in the October issue of the journal Physical Review A – Rapid Communications.

2 comments
2 comments
Facebook User
This is Great or our BHIM Project.
PaulYak
A great pity Pharma corps ganged up on Dr. Royal Raymond Rife! He stated (After many life successes), motorboat engine that won speed endurance records held for years, but no one will publicly acknowledge him. He worked Zeiss Optics and researched at German university where gained doctorate honourably.
He then researched disease identification/treatment, first job was to be able to view living tissue/organisms. Read his story. When Big pharma corps gang up to get rid of you, all the while asking none of them for funds as was friends with one of richest industrialists in states Timken, he saved this man's wife when best doctors could not, why he trusted Rife.
IF any of you work with microscopes/disease treatment, don't allow big pharma to bury Rife's lifes work.