PURISIMA, Dio Mark AngeloDate Submitted: 02/08/2013
Experiment No. 9
AGAROSE GEL ELECTROPHORESIS OF DNA
Agarose is a polymeric cross-linked polysaccharide extracted from the seaweed agar. Agarose is used widely in gel electrophoresis because it gels at a lower temperature, does not contain the inhibitors of virus growth frequently present in agar, and has more uniform pore size than that of agar. It is also easily poured and does not denature the samples. In agarose gel electrophoresis, DNA or RNA fragments are separated or isolated according to their size and electrical charge.The negatively charged nucleic acid molecules move through the agarose matrix with the assistance of an electric field. The genetic material is negatively charged, and will move towards the anode when current is passed through. The shorter molecules migrate faster than the longer molecules. The use of electrophoresis buffer in the making of the agarose gel is to establish a constant pH and to provide ions to support the conductivity. There are three common buffers used in agarose gel electrophoresis. They are Tris-Acetate-EDTA (TAE), Tris-Borate-EDTA (TBE) and Tris-phosphate. For this experiment, the best choice of buffer to use is TAE. The result of our experiment showed no bands. The reasons can be whether the concentration is either very low or DNA is not present at all. This may occur if students punctured the well while loading their DNA.
Results and Discussion
Gel electrophoresis is a method for separation and analysis of macromolecules (DNA, RNA and proteins) and their fragments, based on their size and charge. Agarose (agarose gel) is a polymeric cross-linked polysaccharide extracted from the seaweed agar. The agarose forms a porous...