ucleic acid precipitation
Posted 29 January 2002 - 08:59 AM
Would anyone out there be able to tell as to why alchohols like isopropanol or ethanol are used to precipitate nucleic acids, and also, why is the precipitation done at low temperatures
Posted 29 January 2002 - 09:44 AM
Posted 29 January 2002 - 08:41 PM
For the temperature, it is simply because it reduce the solubility (in general) of dissolved substances. So, it helps to precipitate things (DNA, and unfortunately, salts...). Someone else has given a more in-depht point of view for this explanation.
Posted 29 January 2005 - 08:50 AM
Posted 30 January 2005 - 04:47 PM
DNA is soluble in water because the water molecules intercalate into the phosphate backbone of the DNA and thus maintain it in a soluble state. When you add salt and alcohol you are essentially removing the water molecules and teh DNA then precipitates.