The Nobel Prize in Chemistry for 2014 was decided to be awarded to
Eric Betzig Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA, US;
Stefan W Hell, Max Planck Institute for Biophysical Chemistry, Gottingen, and German Cancer Research Center, Heidelberg, Germany and
William E Moerner, Stanford University, Stanford, “
for the development of super-resolved fluorescence microscopy.”
The development has surpassed the limitations of the light
microscope. For a long time optical microscopy was held back by a
presumed limitation: that it would never obtain a better resolution than
half the wavelength of light. Helped by fluorescent molecules the Nobel
Laureates in Chemistry 2014 ingeniously circumvented this limitation.
Their ground-breaking work has brought optical microscopy into the
nanodimension.
In what has become known as nanoscopy, scientists visualize the
pathways of individual molecules inside living cells. They can see how
molecules create synapses between nerve cells in the brain; they can
track proteins involved in Parkinson’s, Alzheimer’s and Huntington’s
diseases as they aggregate; they follow individual proteins in
fertilized eggs as these divide into embryos.
It was all but obvious that scientists should ever be able to study
living cells in the tiniest molecular detail. In 1873, the microscopist
Ernst Abbe stipulated a physical limit for the maximum resolution of
traditional optical microscopy: it could never become better than 0.2
micrometres. Eric Betzig, Stefan W. Hell and William E. Moerner are
awarded the Nobel Prize in Chemistry 2014 for having bypassed this
limit. Due to their achievements the optical microscope can now peer
into the nanoworld.
Two separate principles are rewarded. One enables the method
stimulated emission depletion (STED) microscopy, developed by Stefan
Hell in 2000. Two laser beams are utilized; one stimulates fluorescent
molecules to glow, another cancels out all fluorescence except for that
in a nanometre-sized volume. Scanning over the sample, nanometre for
nanometre, yields an image with a resolution better than Abbe’s
stipulated limit.
Eric Betzig and William Moerner, working separately, laid the
foundation for the second method, single-molecule microscopy. The method
relies upon the possibility to turn the fluorescence of individual
molecules on and off. Scientists image the same area multiple times,
letting just a few interspersed molecules glow each time. Superimposing
these images yields a dense super-image resolved at the nanolevel. In
2006 Eric Betzig utilized this method for the first time.
