I have stumbled here from slashdot. I have been doing electrophoresis (agarose and PAGE) for over 20 years now. Some comments about the discussion on this page:
1. You can remove agarose from the straw. Agarose should be relatively concentrated (>1% for most types). Then use a syringe with a blunt needle and push water around the wall. Agarose tube will slide out. This takes some practice.
2. There are multiple reasons for slab gel, as oposed to tube. Primary ones are: a) ability to compare samples when run on parallel tracks in the slab; b) easy preparation/analysis.
3. Polyacrylamide gels are hard to make in an open atmosphere (not between 2 pieces of glass)-oxygen in the air inhibits polimerization.
4. DNA fingerprinting and gel electrophoresis are not the same. The latter is a method of separation of molecules by charge, and not in intself "fingerprinting".
5. No, one cannot substitute a $1000 piece of equipment with a $50 worth of parts. While DIY is a perfect way to get to proof of concept or to play with it, $1000 equipment costs this much because it provides precision, reliability and reproducibility not achievable with $50. BTW, commercial power supply that will do what you are describing will cost ~$200, not $1000. The gel box as described was and still is used in many labs with the exception of the wire used to provide current to the solution. In mol.bio. labs people use platinum wire.
Drinking straw electrophoresis!
1. You can remove agarose from the straw. Agarose should be relatively concentrated (>1% for most types). Then use a syringe with a blunt needle and push water around the wall. Agarose tube will slide out. This takes some practice.
2. There are multiple reasons for slab gel, as oposed to tube. Primary ones are: a) ability to compare samples when run on parallel tracks in the slab; b) easy preparation/analysis.
3. Polyacrylamide gels are hard to make in an open atmosphere (not between 2 pieces of glass)-oxygen in the air inhibits polimerization.
4. DNA fingerprinting and gel electrophoresis are not the same. The latter is a method of separation of molecules by charge, and not in intself "fingerprinting".
5. No, one cannot substitute a $1000 piece of equipment with a $50 worth of parts. While DIY is a perfect way to get to proof of concept or to play with it, $1000 equipment costs this much because it provides precision, reliability and reproducibility not achievable with $50. BTW, commercial power supply that will do what you are describing will cost ~$200, not $1000. The gel box as described was and still is used in many labs with the exception of the wire used to provide current to the solution. In mol.bio. labs people use platinum wire.