03 Jul 2013
Enables novel optical scanning approach to biological analysis.
Combined with fluorescence microscopy, this new approach has enabled them to obtain detailed optical images of a mouse brain at an unprecedented resolution.
In recent years, teams in both the USA and Japan have reported a number of new techniques to make biological samples transparent, which have enabled researchers to look deep into biological structures such as the brain [of a mouse].
“However, these clearing techniques have limitations because they induce chemical and morphological damage to the sample and require time-consuming procedures,” said Dr. Takeshi Imai, who led the RIKEN study.
SeeDB, an aqueous fructose solution, which Imai developed with colleagues Drs. Meng-Tsen Ke and Satoshi Fujimoto, is said to overcome these limitations.
Using SeeDB, the researchers have been able to make mouse embryos and mouse brains transparent in just three days, without damaging the fine structures of the samples, or the fluorescent dyes they had injected in them.
The researchers could then visualize the neuronal "circuitry" inside the mouse brain, at the whole-brain scale, under a customized fluorescence microscope without making mechanical sections through the brain.
Dr. Imai and colleagues report that they were also able to visualize in three dimensions the wiring of mitral cells in the olfactory bulb, which is involved the detection of smells, at single-fiber resolution.
"Because SeeDB is inexpensive, quick, easy and safe to use, and requires no special equipment, it will prove useful for a broad range of studies, including the study of neuronal circuits in human samples," explain the researchers.
About the Author
Matthew Peach is a contributing editor to optics.org.