Homemade ECL imaging? - Can I make a digital blot capture system for my home? (Feb/12/2009 )
Using an old digital camera and our UV light, I made a 'gel documentation' system for our PCR products and other DNA work - it works great.
Can I do something similar for ECL Westen blots? I think the max shutter opening on my Canon A85 is 15 seconds, that may not be enough time? Has anyone done such a thing? I'm willing to by a new camera (one that allows longer shutter times). Would it work?
Right now, we go in our makeshift darkroom and expose the membrane to film, develop it, re-expose (depending on intensity of bands), develop,.... I envision, just placing the membrane in the darkroom in my homemade set up, clicking on the computer connected to the camera and it automatically takes many pictures with different exposure times! That would be great (plus it would be color which looks cool.... do I need any filters, maybe it wouldn't be color). For the DNA/RNA gels, I have a yellow filter.
Even if you don't have such a setup, let me know what you think?
It should work so long as you can consistently get bright bands on your westerns. The main limitation will be the sensor of the camera, try getting a prosumer (1.5 cm2,/sup> sensor) or SLR type camera (2.5+ cm2 sensor) if you can , they have much larger sensors than the average digital camera (0.5-1 cm2) and so can gather more light.
bob1 on Feb 12 2009, 03:33 PM said:
So, in this case, do you think I would need a filter (like I do for my homemade ethidium bromide agarose gels)? I'm thinking no... but heck I'll try it out and see.
No, you shouldn't need a filter, the filter is only there for the EtBr systems to reduce the effect of the UV on the camera and to lower the background.
We had tried something like that in the past. We have an older model CCD camera for the microscope which we tried using for ECL. Long involved story which ended up not working. However, I would try some of the settings for night photography where you can hold the shutter open to take pictures of movement of stars and traffic. Then it will just be trial and error to see how long you need to hold it open.
Let us know how it works out.
I don't think our cameras' shutters can stay open more than 15sec. So I guess I'll have to wait until I can find a cheapo camera that'll do that (you know the economy right now, I don't want to go out and buy one just to have it not really work for capturing ECL pics).
If anyone out there has done this, and it works then I would definitely be up for buying a camera (it's less than the 10s of thousands for those imager things!).
Beverly on Feb 23 2009, 12:28 PM said:
Let us know how it works out.
Using a friend's Canon 40D SLR, with 50 mm F1.4 lens at 1.5 feet, iso setting of 1600, and a 4 min exposure, I obtained an ECL image equivalent to a 10 sec exposure to sensitized (preflashed) Kodak X-AR film. This was without employing noise reduction on the camera. Based on recent improvements with full frame CMOS sensor technology (Canon 5D mark II or Nikon D700), and using optimal noise reduction built into these cameras, one should be able to decrease camera exposure time by 5X vs the 40D; i.e., the same 10 sec film exposure should only require a 50 sec or so exposure with the newer cameras. The cost of these newer cameras with lens is about $3000 but avoids the time, costs , and chemicals involved in film processing. The linear response range of the cameras is also about 50X greater than film.
Wow, that sounds cool. So how do you know the linear response range of the cameras is 50x greater (and what exactly does that mean...I think I know, but just would like clarification). This sounds like a real possibility. I may think about buying a 40D (less than 100 bucks and I could do away with film and chemicals, that would be great!).
Can you give me any more wisdom on the subject?
dwaswad on Mar 10 2009, 02:09 PM said: