A simple and effective separation and purification procedure for DNA fragments using dodecyltrimethylammonium bromide.
In this work we describe a simple two step separation procedure for the separation and purification of short DNA fragments. The first step involves precipitating the DNA using the cationic surfactant dodecyltrimethylammonium bromide. Dodecyltrimethylammonium bromide, unlike cetyltrimethylammonium bromide will not precipitate DNA before complexation is complete thus providing a high purity DNA. The second step involves dissolution of the DNA-dodecyltrimethylammonium complex in 75% ethanol, followed by precipitation of the Sodium-DNA salt, by titrating in a salt solution. This method is particularly suited to purification of short fragments as it does not require high salt concentrations in the ethanol precipitation step, which can be damaging for short DNA. The ability of dodecyltrimethylammonium bromide to remove ethidium bromide from intercalation sites on the DNA is also discussed
McLoughlin
D M
DM
Irish Centre for Colloid Science and Biomaterials, Department of Chemistry, University College Dublin, Belfield.
O'Brien
J
J
McManus
J J
JJ
Gorelov
A V
AV
Dawson
K A
KA
D011232:Chemical Precipitation; D004247:DNA / Q000302:isolation & purification*; D004996:Ethidium; D007364:Intercalating Agents; D009691:Nucleic Acid Denaturation; D000644:Quaternary Ammonium Compounds; D013501:Surface-Active Agents
D007364:Intercalating Agents; D000644:Quaternary Ammonium Compounds; D013501:Surface-Active Agents; D004247:DNA; D004996:Ethidium; C022806:dodecyltrimethylammonium