Steven Chu Breaks Record for Highest-Resolution Optical Imaging, Cracking Nanometer Limit

The FPALM system of microscopy developed by Sam Hess at the University of Maine can image single molecules, and has been around for years. This isn't new technology, and therefore really isn't a breakthrough. Chu isn't the first one to come up with this, as Hess and a few other independent researchers developed their own systems. Another system very similar to FPALM (Fluorescence Photoactivation Localization Microscopy) is STORM (Stochastic Optical Reconstruction Microscopy), which uses the same ideas.

From a paper I've written:
Hess, Girirajan, and Mason demonstrated excitation using photoactivatable green fluoroescent protein (PA-GFP) molecules which are initially “dark,” meaning they are weakly fluoresced. It is at this point that fluorescence and visualization take place at first one, then another excitation wavelength. Once this is done, a small number of randomly photoactivated molecules are localized using methods for single-molecule detection. To improve the result, the randomly photoactivated molecules are separated from each other by several times the resolution, as determined by the Rayleigh criterion (Hess et al.4259).
Once a randomly-determined number of photons are retrieved from the molecules, each of the molecules used is then photobleached. This process of photobleaching causes the individual molecules to proceed to a state of non-fluorescence, at which point they are “dark” and will no longer fluoresce. Because the molecules that have been photobleached can no longer be excited to fluoresce, a very accurate image can be assembled without fear of overlapping molecules. Photoactivation times for the fluorophores used by Hess et al. with FPALM were not significant due to the fact that the entire field was being imaged at once. However, this photoactivation time is significant in other methods, as it becomes more difficult to increase the activation rate (Hess et al.4269).

Source: Hess, Samuel T., Thanu P K Girirajan, and Michael D. Mason. "Ultra-High Resolution Imaging by Fluorescence Photoactivation Localization Microscopy." Biophysical Journal 91.11 (2006): 4258-272.

This is very exciting, interesting to see if there are any new discoveries from this..

@chaseea0

What Dr Chu is stating that they have done is quite a bit higher resolution than the 20 nM that the method you are describing can do.

@chaseea0 This certainly is new technology as it appears to be substantially different from STORM or FPALM. For one, it doesn't appear to require any type of fluorescent tagging. It's also higher resolution.

Scientific pursuits are all about using the knowledge of other scientists and taking whatever steps are necessary for advancement in not only technology, but our understanding of it. We cannot allow ourselves to only focus on credibility or "who did it first". We have to work collectively to achieve a common goal, no matter how insignificant the findings may be. One small step can be just a small step. However, a LOT of small steps can lead to an incredible breakthrough. Let's congratulate Dr. Chu for his hard work and determination.

"Motivation and dedication are the tools that drive the engine of excellence" - Me