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Hey folks!

I just got back from the Society for Neuroscience meeting in San Diego, 
where Leica was giving a demo of it's Stimulated Emission Depletion 
(STED) instrument.

Seeing it was an interesting experience.  The microscope appeared to 
improve resolution of some specimens (specifically, histones) by a 
factor of probably 5-fold--there was a very pronounced improvement and 
unless their scale bar was lying, they seemed to be down into the 50 nm 
range.  It did not seem to offer as much improvement on their muscle 
specimen, and photobleaching was a serious problem on that one as well 
when they went up to high zooms.

The STED module works only for one color (far red) and does not work 
well with all fluorophores (--specifically, Cy5 apparently bleaches too 
fast to be useful).  The fluorophores they recommended are the ATTO 647 
and 655 dyes.  Although STED provides an improvement in x-y resolution, 
there's little or no improvement in the z-axis resolution.

The instrument is essentially a Leica multiphoton microscope with the 
STED unit as an attachment.  It can be used in single-photon, 
multiphoton or STED modes.  Price is $1.3 million USD.

I'd be interested in hearing from other folks who talked to Leica about 
this machine and who saw one of the demos.  If I were buying one of 
these items, it'd be worried about it suddenly becoming obsolete (as 
happened with some of the early 2-photon instruments) due to some new 
development in the pipeline.  Does anyone have any sense of how likely 
that is?  I'd also be concerned about how suited it is to all 
preparations--will it work only with the strongest labeling?  Do the 
ATTO dyes require particular mounting media?

Thanks in advance!

Martin
-- 
Martin Wessendorf, Ph.D.                   office: (612) 626-0145
Assoc Prof, Dept Neuroscience                 lab: (612) 624-2991
University of Minnesota             Preferred FAX: (612) 624-8118
6-145 Jackson Hall, 321 Church St. SE    Dept Fax: (612) 626-5009
Minneapolis, MN  55455             E-mail: martinw[at]med.umn.edu