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New Microscope Reveals Ultrastructure of Cells
An anonymous reader writes "For the first time, there is no need to chemically fix, stain or cut cells in order to study them. Instead, whole living cells are fast-frozen and studied in their natural environment. The new method delivers an immediate 3-D image, thereby closing a gap between conventional microscopic techniques. The new microscope delivers a high-resolution 3-D image of the entire cell in one step. This is an advantage over electron microscopy, in which a 3-D image is assembled out of many thin sections. This can take up to weeks for just one cell. Also, the cell need not be labeled with dyes, unlike in fluorescence microscopy, where only the labeled structures become visible. The new X-ray microscope instead exploits the natural contrast between organic material and water to form an image of all cell structures. Dr. Gerd Schneider and his microscopy team at the Institute for Soft Matter and Functional Materials have published their development in Nature Methods (abstract)."
Indeed. Fast freezing has advantages in that, theoretically, a sufficiently instantaneous freeze could preserve tertiary and quaternary structures. In practice the laboratory technique is no where near that good.
Similar concepts apply to pharmaceutical development based upon data gleaned from enzymatic assay or even cell cultures of only one cell type. There is a whole lot that goes on in the surrounding environment that makes a heckuvalot more difference than just the one thing under the microscope.
Take creamer in coffee, real cream. Do not add it to hot coffee or the coffee will taste burnt and, likely, you will have gas from it. Hot coffee denatures cream. Allow the coffee to cool before adding cream. Cold is no different. When enzymes and proteins go from normal temperature to super-frozen they constrict and often fold differently.
Still... interesting technique and I am positive there will be good applications in the future.
the NPG electrode was replaced with carbon blac