I'm almost sure the one present in my lab (which a student use it) is the same as this MecanUSA twin-arm LED. I'm not a 100% sure because I do not use it to screen the transgenic mosquitoes since I don't work with them, but on monday I'm going to check it out and give you the right answer.

sorry, I can't help you

Hi Stephen,

Thanks. We already have a (very nice) Olympus stereomicroscope. We could fit the scope with Olympus epifluorescent optics, but that will cost about $10,000.

The items I listed above are external LED light sources and filters that can be fitted to the scope. They are MUCH cheaper ($500-$1,000). I just wanted to know if anyone has used them for transgenic screening.

Frankly, I'd be really interested if anyone has used the transmitted LED, as its half the price of the twin arm (about $500).

Yes, an LED should work - they are often used for fluorescent applications. In response to the comment above, UV excitation will work for certain probes, but it depends on the excitation wavelength of your probe of interest. If you need visible excitation, LED is certainly the way to go. I use a fiber arm to deliver white light to my Zeiss stereomicroscope. You will still need a band pass filter to eliminate the strong signal from the excitation source, and allow only the fluorescence in which you are interested into the occulars for a sharper image. Hope this helps - let me know how it turns out.

Actually I'm setting up a cheep version using a stereoscope for some quick screens. Depending on how intense your signal is you can get by with a blue laser pointer and a 515nm long pass filter if your using GFP as your indicator (about $50 from Edmund Optics). The laser pointer is a little off the optimal wavelength for GFP (405nm while GFP is excitation is around 450 nm) and a very targeted working space, but it works for doing quick screens. You could give it a try, total cost about $70, if it doesn't work for what you need then get the LED, the filter should still work, and you have a laser pointer for presentations.

Forgot to mention that I have used something very similar to the twin arm and it too works well. Though again, it is very dependent upon where you signal is on/in the organisms. The larger the structures, more intense the signal the better your luck will be with these cheeper systems.

Beware of laser pointers. If too strong you will harm your eyes. Be very careful.

This approach looks fantastic. We do a lot of work with percoll density gradient collection of GFP cells - but just collecting the right band is mostly done by faith. Using an LED light source to id the right band could really help.

Hi Rob,

Thanks. I've considered the laser pointer technique already (its nice because you can use a blue pointer for GFP or a green pointer for DsRED). While I think it'll work for transgenic mosquitoes with the 3xP3 eye promotor, it won't work for some of our other applications. I will try it anyway, just because the laser pointers are cool and useful :)

Jason,

It depends on the stereo microscope. We use these http://www.spectraservices.com/UFIS.html around $10K without the scope—works with only certain ones.

or

http://www.kramerscientific.com/products.html

Let me know if this helps? or Call me for more information

Bill Talero 585-265-4374 Extn 24 or Cell 561-252-3191

Thanks Bill. The point is to avoid spending $10K :) But I appreciate it.

Do you have a budget? We can possibly look at alternatives. Do you mind if our Microscopist contacts you? I am certain he will be able to get it done within budget.

Hi BIll,

$1,000-$2,000 at most, for both GFP and DsRED.

Update, we decided to try the Mecan transmitted LED and filter for GFP detection (it was cheaper by about half compared to the twin-arm) on our Olympus dissecting scope. Works great.

We're going to order the DsRED LED now. Since they sent us the filter assembly and both GFP and DsRED filters already, we only have to purchase the LED.

Total cost to outfit the scope for both GFP and DsRED detection, about $1,100 including shipping.

Hello Jason,

I am now looking for a similar stereoscope attachment as you were a few years ago in this Q&A feed, with UV light. I'm curious if you'd recommend the Mecan transmitted LED and filter set you were planning on purchasing in 2012, now that you've tried it out. There is also a NIGHTSEA stereoscope fluorescence adapter available through Electron Microscopy Sciences. Do you happen to have any experience or recommendations for this (or other comparable) equipment? 

NIGHTSEA here. Just stumbled on this thread. Teagan, feel free to contact me to discuss your application. There are a lot of people using our Stereo Microscope Fluorescence Adapter system for screening/sorting and other fluorescence tasks, and we do offer a true UV illuminator as one of our five excitation options. Go to nightsea.com for more info and our contact info.

Thanks Charles. I actually tried the NIGHTSEA UV scope attachment last week and it is fantastic! I especially appreciate that your company provided a 5-day trial period, so that I could be sure the system was appropriate for my lab needs. One question - do I need to be concerned about skin and/or eye damage when the UV magnetized filter is in place, over long periods of dissecting? I'm wearing gloves, but I'm not wearing extra eye protection.