Usman Qazi |
To build such a system most economically, I’d like to
get some opinions on component prices. Primarily, I am looking for a used epifluorescence
microscope that can be equipped with a piezo-electric stage. My initial web
searches have not yielded much on the used equipment market. But at the minimum, I’d like to salvage a suitable ‘shell’
from somewhere. The more optics there are on it, the better. If anyone has some ideas to share regarding the other
components needed to build a STED system, please share by all means. For
example, is it better to go for a blue diode or a Ti:Sapphire laser? I haven’t seen a STED system in action. But it could
be useful for pathologists in a developing countries where EM’s are very costly
to buy and maintain. I used to do 3DEM, but need to adapt myself to the
environment here. Regards, Usman Qazi, PhD School of Science and Engineering LUMS DHA, Lahore Cantt, Pakistan sse.lums.edu.pk |
Rietdorf, Jens |
Dear Usman, It might be more simple and
cheaper to build an instrument exploiting the PALM/STORM or RESOLFT methods
to increase resolution. Best, jens From: Confocal Microscopy
List [mailto:[hidden email]] On Behalf Of Usman Qazi To build such a system most economically,
I’d like to get some opinions on component prices. Primarily, I am looking for a used
epifluorescence microscope that can be equipped with a piezo-electric stage. My
initial web searches have not yielded much on the used equipment market. But at the minimum, I’d like to
salvage a suitable ‘shell’ from somewhere. The more optics there
are on it, the better. If anyone has some ideas to share regarding
the other components needed to build a STED system, please share by all means.
For example, is it better to go for a blue diode or a Ti:Sapphire laser? I haven’t seen a STED system in
action. But it could be useful for pathologists in a developing countries where
EM’s are very costly to buy and maintain. I used to do 3DEM, but need to
adapt myself to the environment here. Regards, Usman Qazi, PhD School of Science and Engineering LUMS DHA, Lahore Cantt, Pakistan sse.lums.edu.pk |
In reply to this post by Usman Qazi
Lets be clear from the start that STED microscopes are likely to be more costly and more difficult to maintain than electron microscopes. EM technology is mature, low-end systems are cheap, and maintenance is straightforward. Alignment accuracy required for a STED system is probably 2 orders of magnitude higher than alignment of a TEM.
Having said that, it's also true that starting from nothing you probably have more chance of building a useful homebrew STED system than you do of building a homebrew TEM. Your first decision is whether to build a system like the Leica, which offers super-resolution only in XY, or to follow Stefan Hell's original scheme and seek super-resolution in all 3 dimensions (but markedly better in Z). This all comes down to the apodization scheme for the depletion spot. I'd vote for the Leica way, but their system is not the only way to do it. I think, for example, you could get a 'doughnut' spot with a conical lens. Tony Wilson, at Oxford, could probably advise on this. You also ask about lasers. Again, to get a robust system your depletion beam needs to be orders of magnitude stronger than your excitation beam. That, of course, is what made Leica go to a Ti-S for their depletion beam (plus the fact that, living as they do in the commercial world, it means you can immediately use the same microscope for two-photon imaging). But Ti-S lasers are very expensive, and if you went to shorter wavelengths you could get equivalent resolution with a smaller difference between the excitation and depletion beam. You will need to get your suppliers to give you the required synchonizations of the pulses. It's all doable. But I'd have to say my advice would be don't. If you want to get a cheap way into super-resolution then contact Trevor Smith at Melbourne University who has developed a very clever and simple structured illumination system (based on Mats Gustafsson's research) using an everyday video projector as the illumination source. It won't match STED in resolution, but it will go well beyond Rayleigh and, most importantly for you, it's relatively straightforward. Guy Optical Imaging Techniques in Cell Biology by Guy Cox CRC Press / Taylor & Francis http://www.guycox.com/optical.htm ______________________________________________ Associate Professor Guy Cox, MA, DPhil(Oxon) Electron Microscope Unit, Madsen Building F09, University of Sydney, NSW 2006 ______________________________________________ Phone +61 2 9351 3176 Fax +61 2 9351 7682 Mobile 0413 281 861 ______________________________________________ http://www.guycox.net <http://www.guycox.net/> ________________________________ From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Usman Qazi Sent: Tuesday, 10 March 2009 12:04 PM To: [hidden email] Subject: used microscope for home-building a sted (super-res) system? To build such a system most economically, I’d like to get some opinions on component prices. Primarily, I am looking for a used epifluorescence microscope that can be equipped with a piezo-electric stage. My initial web searches have not yielded much on the used equipment market. But at the minimum, I’d like to salvage a suitable ‘shell’ from somewhere. The more optics there are on it, the better. If anyone has some ideas to share regarding the other components needed to build a STED system, please share by all means. For example, is it better to go for a blue diode or a Ti:Sapphire laser? I haven’t seen a STED system in action. But it could be useful for pathologists in a developing countries where EM’s are very costly to buy and maintain. I used to do 3DEM, but need to adapt myself to the environment here. Regards, Usman Qazi, PhD School of Science and Engineering LUMS DHA, Lahore Cantt, Pakistan sse.lums.edu.pk No virus found in this incoming message. Checked by AVG. Version: 7.5.557 / Virus Database: 270.11.10/1995 - Release Date: 11/03/2009 8:28 AM No virus found in this outgoing message. Checked by AVG. Version: 7.5.557 / Virus Database: 270.11.12/1998 - Release Date: 12/03/2009 6:23 PM |
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