Low cost DNA gel documentation
Equipment for photographing DNA gels stained with ethidium bromide (or other fluorescent dyes), doesn’t have to cost thousands of dollars. These days, great pictures can be obtained with a standard digital camera and an orange filter. Here’s how.
You will need:
- A digital camera
- A Cokin orange filter 002A or similar (This does not have to fit onto the camera, a square filter will do.)
- A polystyrene ice bucket with a thick (3-5cm bottom)
- A UV transilluminator
To build it:
- Cut a hole in the bottom of the box that is big enough for the camera lens to fit into.
- Tape the filter over the hole, inside the box.
- Set the camera flash to off and the mode to black & white.
- Push the camera’s lens tube into the hole (or place the camera lens over the hole if there is no lens tube). Depending on the shape of your camera, you may have to modify the box to ensure that the camera is pointing straight into the hole.
- Place your DNA gel onto the transilluminator and put the box over the gel.
- Turn the transilluminator and the camera on. You should now be able to see the stained DNA on the gel in the viewfinder of the camera.
- To get a quality picture and good detection limits you will have to play around with the ISO, shutter speed and aperture. This will be specific to your camera, but the setting ISO 200, Shutter speed 1/3, Aperture 8.0 worked for me so may be a useful starting point for you.
Update: Here’s a schematic diagram that shows how the whole thing should fit together. Let me know if you have any comments or questions.
molecular biology
I sure wish I’d known this when I was a graduate student! Recording gels digitally was a 20 minute procedure in our lab and the quality was never that good.
By the way, welcome to the DNA Network!
This is very interesting and usefull.
I don’t know how to choose the filter. If I want to use a filter that green light can pass through, but blue light cannot, What characteristic should the filter be?
Hi -
I believe that you would want a green filter for that - such as the Kodak green CC filter series (see http://micro.magnet.fsu.edu/primer/photomicrography/ccfilters/ccgreen.html)
Thank you very much!
You don’t even need the UV transilluminator. If you’re using sybr Green or sybrSafe, you simply use blue LEDs like a bicycle lamp or a strong torchlight.
Thanks! Your system seems like just what I need, but do you mean polystyrene ice bucket? or the polyurethane ice buckets they sell?
Hi Kate,
I was thinking of the polystyrene boxes that enzymes are normally delivered in (packed in dry ice). The reason these are best is that they have a thick bottom.
This means that, after you make a hole in the bottom of the box, the camera lens tube can be pushed through, and the filter taped over the other side of the hole.
I have added a diagram to the article to illustrate.
Nick,
Thanks. Actually, do you mean styrofoam?
I’ve been really busy this week but I mean to try the method as soon as I can, maybe today.
Thanks,
Kate
Hi Kate
Yes, styrofoam = polystyrene
Good luck with trying out the method. Be sure to post your results here!!
I made a gel doc using syrofoam box deep yellow 15 filter and my little digital camera. It seems to work best if I take the pictures in color, then convert to bw on the computer. Auto exposure and focusing seem OK. The problem it has is that there seems to be a reflection of the filter in the middle of the picture. It’s less obvious when I convert the picture to bw, however.
Is there a way to get rid of the reflection?
Hi Kate
I would suggest two things:
1) Modify the box so that the camera lens rests on the filter (i.e. so there is no gap between the lens and the filter)
and/or
2) Make sure that no external light gets in i.e. make sure the lens/lens tube fits snugly in the hole without letting any light in. If required, plug up any gaps with cotton wool or something.
Let me know if this fixed it.
Max, have you actually used a blue LED lightsource for visualizing bands with sybrsafe? sounds like a great idea. can you describe what you used and how well it worked? is it bright enough for photography, and do you need more filtration than the orange filter specified at the beginning of this thread?
thanks,
ted