Science Buddies: "Ask an Expert"

I have now attempted this experiment twice, the first time, the box put it in was a little big and was a failure on my part. The second time I did it with a normal size soap box, but both times, a weird cloudy film would come over top of the box and would kind of bubble so I couldn't see the colors. Now I have two things that I think it might be. 1: In the regular instructions, it says to use (for the solutions) deionized water, but in the video, it says to use bottled water and clearly in the video it worked. 2: whenever I try to pipette the food coloring into the gel, sometimes I accidentally squeeze it too hard and then it kind of bubbles, leaving space in between the bottom of the container. It could be bleep completely different, or I could just be doing the entire thing wrong. Any reply would be great. Thank you.

Picture of what the film over top of the coloring looks like:

Moderator note: Project: https://www.sciencebuddies.org/science- ... ifying-dna

Hi there,

The problem may be with the bottled water compared to the de-ionized water. The de-ionized water is distilled specifically so that the minerals which can be present in bottled or tap water don't interfere with the Gel Electrophoresis process where samples of DNA/RNA/proteins run through the Gel. For pipetting, you probably want to use a very small amount. When I ran this experiment with real DNA, I used a micro-pipette while pipetting around 5-10 microliters worth of solution. You most likely want to both remove any bubbles from your pipette and use less solution. To remove bubbles from your pipette, you can try initiating the pipetting while the pipette tip is in the solution. If there are bubbles, you can just retry pipetting. Hope this helps.

Thank you!