1% agarose is usually used as electrophoresis support. The pH value of electrophoresis buffer is between 6 and 9, and the optimum ionic strength is between 0.02 and 0.05. 1% agarose is usually used as electrophoresis support. Agarose gel can distinguish DNA fragments with a difference of about 100 bp. Although its resolution is lower than that of polyacrylamide gel, it is easy to prepare and has a wide separation range.

The range of DNA separation by ordinary agarose gel is 0.2 ~ 20 kb, and DNA fragments as high as 107 bp can be separated by pulse electrophoresis.