A Simple Sugar Solution Can Make Tissue Transparent

It's difficult to believe it, but it took just three days marinating in a sugar-water solution to turn the opaque tissue pictured on the left into the clear example on the right.

Called See Deep Brain (SeeDB), the new technique uses a combination of fructose, water and small amounts of other chemicals to reduce the amount of scattering that occurs when light passes through biological tissue. Described in detail in this week's Nature Neuroscience, the technique will allow scientists to probe the inner workings of the brain and other organs.

There have been a few other methods proposed for what's now become known as "optical clearing", but what's neat about SeeDB is that it's compatible with the dyes that are often used to trace neurons in tissue preserved in formaldehyde. As well as, you know, being non-toxic, which is also handy. Soon, then, scientists will be optically peering through samples without having to chop them up—and that could yield all kinds of exciting results. [Nature Neuroscience via Science]