Gel extraction
Gel extraction is performed to recover nucleic acid fragments of interest from an agarose gel.
The first step is to excise the agarose gel containing the fragment of the desirable size. The gel is then placed inside a purification column that contains a silica membrane. Then, a binding buffer containing chaotropic agent is added to dissolve the agarose gel, denature proteins, and promote DNA binding to the silica membrane. In order to enhance the gel dissolving process, the mixture is incubated at 55-60oC. Other remaining residues are removed using the wash buffer. The last step is the addition of the elution buffer to elute the purified DNA from the purification column.