Electroelution

Using this method, DNA fragments can be recovered from a particular region of agarose or polyacrylamide gels. The gel piece containing the fragment is excised (cut out from the whole gel) and placed in a dialysis bag with buffer. Electrophoresis causes the DNA to migrate out of the gel into the dialysis bag buffer. The DNA fragments are recovered from this buffer and purified, using phenol–chloroform extraction followed by ethanol precipitation. This method is simple, rapid and yields high recovery (75%) of DNA fragments from gel pieces.^[3]

Preparative native PAGE yields more than 95% recovery of metalloproteins. Proteins are continuously eluted from a gel column and separated in different fractions according to their isoelectric points.^[2]