Hello! Thanks for coming to us for help!
"Can gel electrophoresis separate the proteins in peanuts and peas?" Yes, this is possible. In summary, you can use a protocol to extract the protein material from peanuts and peas. You would then load the sample onto a gel and run it very much like the description provided on the Science Buddies project page you cite above. In the context of a common molecular biology lab setting this would be easy and straightforward to do. You would have all the materials you need. Can you make this type of preparations at home? For some of the aspects of the project, yes. I need to think some more about the details so that I can help you further. Why don't we do some research online and see what we find? I will work on this during the weekend. In the meantime, I would like to give you some clues as well as give you a list of the things we need to research or get more info about.
What I know for sure...
1. Can I use agarose gels to separate proteins? Yes. You can use agarose gels to separate big/large proteins.
2. How can I set up agarose gel electrophoresis? You have the answer to this- http://www.sciencebuddies.org/science-f ... p028.shtml
Is this the kit you purchased?
What I need more info on...
3. Can we design a protocol to extract protein from peanuts etc that does not use any hazardous materials that are also easily available commercially to the common citizen?
4. Once we run the gel we need to have a way to stain it to see the "data" or where the proteins are...can we do this using a protocol that does not use any hazardous materials that are also easily available commercially to the common citizen?
If you wanted to do a similar set of experiments but looking at DNA, questions 3 and 4 would still need to be answered. Usually DNA is visualized using dyes that intercalate into the DNA (and considered mutagenic, lead to mutations). To visualize this type of staining one would need UV light as well. These things are not safe when done outside the laboratory setting. For this reason these type of dyes are probably very hard to obtain outside of the context of the research lab. Also, if you were succesfull at doing this with DNA, you would, essentially be isolating really large pieces of DNA, and you would see "blobs" on your gel after visualizing it. I am not sure you could do much in terms of data interpretation with those pieces of data. This would also sort of be the case with detecting/visualizing overall protein context without more refined specificity.
I will start working on questions 3 and 4 ASAP. In the meantime, you can do the same and we can compare notes. Also, you may want to continue thinking about what other things you'd like/could look at in the context of using electrophoresis as a technique. A potential idea would be- sticking to samples that, intrinsically, have a way to be detected (visualized) and you do not have to find ways to stain for them. Beets have a very strong color to them- they contain natural dyes that can be separated using techniques like chromatography and electrophoresis. This is the same concept as with food coloring. Can you think of another natural product that has a strong color? Chances are that its "dyes" can also be separated into its different components. You could then compare the electrophoresis patterns. Another idea-You could pick two natural products that share a similar color and see if their "dye components" are similar?
Hope this helps!
What do you think?
How does this sound?
PS> Some of your other questions-
"If not, what can I use that would be interesting to compare DNA samples that would be ethical for science fair?"
See above, I think I answered it. Let me know if it is not clear.
"How would I prepare my samples and what other materials would my mom need to buy that aren't included in the kit?"
This is one of the things we need to research.