Showing posts with label microscopy. Show all posts
Showing posts with label microscopy. Show all posts

Wednesday, October 12, 2011

Clarifying brain structure, literally


Nature Methods
 
8,
 
793
 
(2011)
 
doi:10.1038/nmeth.1720
Published online
 


A fluorescence-compatible tissue-clearing reagent enables light microscopy–based imaging deep in the mouse brain.

In The Invisible Man, a science fiction novella by Herbert G. Wells, the protagonist is a scientist who finds a way to make the human body invisible by changing its refractive index to prevent the bending and reflection of light. In a recent report, Atsushi Miyawaki and his colleagues at RIKEN described the development of a tissue-clearing reagent with similar effects, bridging the gap between science and fiction and enabling fluorescence-based imaging of biological tissues at unprecedented depth and subcellular resolution.

High-resolution microscopy methods and fluorescence-based labeling techniques have enabled the three-dimensional imaging and reconstruction of defined cellular populations in a variety of biological tissues. However, axial resolution and imaging depth are often limited by the intrinsic opacity of biological specimens. For example, in visualizing the mammalian brain, light microscopy–based advances have been confined to the few hundred micrometers under the organ's surface. Alternatively, mechanical sectioning or insertion of minuscule endoscopes can be used to access deeper structures, but such approaches are inevitably laborious, invasive or of limited perspective.

Tuesday, October 11, 2011

My Smartphone Is A Microscope. What Can Yours Do?

From NPR:

I lied. My smartphone isn't a microscope — yet. But there are some smart physicists who want to make that transformation possible very soon, if not for you and me at first, then for doctors who don't have easy access to laboratories.

There are a lot of ways to trick out your smartphone. And if you're an eager Apple fan, the brand-new iPhone 4S will come with fancy apps that use its increasingly sophisticated camera to scan and image the world. A smartphone camera lens can measure objects, help translate words, and even tell you whether your potato chips have been caught in a food safety recall.

But Sebastian Wachsmann-Hogiu and colleagues at the Center for Biophotonics, Science and Technology at the University of California, Davis say a smartphone's camera lens can also serve as a microscope and a spectrometer, which both could be pretty handy for looking at blood samples.

A few years ago, Wachsmann-Hogiu was thinking about creating tools to help doctors do tests right at the site where they're caring for patients, something called "point-of-care testing."

He'd heard about bioengineer Daniel Fletcher's work developing a low-tech mobile microscope called CellScope. But Wachsmann-Hogiu was interested in making something even simpler. And he noticed that when water droplets formed on the top of his iPhone camera, they magnified the image. So he took a tiny lens — just 1 millimeter in diameter — and attached it to the phone to try to get a similar effect.