Microscope Captures 3D Movies of Living Cells

Zothecula writes "In some cases, looking at a living cell under a microscope can cause it damage or worse, can kill it. Now, a new kind of microscope has been invented by researchers from the Howard Hughes Medical Institute that is able to non-invasively take a three dimensional look inside living cells with stunning results. The device uses a thin sheet of light like that used to scan supermarket bar codes and could help biologists to achieve their goal of understanding the rules that govern molecular processes within a cell."

Comments

Not much at Gizmodo

[ColdWetDog]

Just some mindless drivel and a few pics - for a bit more, do a search on "Bessel+beam+plane+illumination+microscopy". Basically, it is a system that uses a narrow collimated light beam that is stepped through a cell to excite photons (it appears that they're using flourescent dyes, not clear if you have to do that), pick up the photons in a detector and reconstruct the image, much like at CT or MRI.

While researchers have been able to use monoclonal antibodies to tag internal bits of cells, you either got fairly poor spatial resolution of living cells because you were imaging the entire cell depth or you got excellent spatial resolution of dead, fixed cells with the obvious issues of stopping a dynamic process. This method, if they can work it out a bit better (resolution doesn't seem to be all that good yet) would combine the advantages of tagging cells at high resolution but using living cells.

Re:Not much at Gizmodo

[Beezleboss]

Nitpicking here but, it's not exciting the photons, it's exciting the electrons in the fluorophores, which as they relax emit a photon of a different wavelength. It also says that they are using two photon microscopy which basically requires the energy from two simultaneous photon interactions with the electron to excite it to the required energy level, so yes the fluorescent probes are necessary. This will also retain the problems that the article claims to remove, namely the damaging of the cells and photobleaching (exciting the fluorophore to a point where it is no longer fluorescent) because light of the same wavelength as previous techniques is still needed to excite the fluorophore and so is still being applied to the cell. The only benefit in this regard is that (probably) less light is applied, so the effects will take longer to appear.