Hello Dears, i know the purpose of isopropenol in DNA extraction, collect the DNA in the form of pellet from the sample. what is the reason and logic we use chilled isopropenol in the extraction of fungus or bacterial DNA.
The use of chilled IPA increases the rate of precipitation of DNA and allows it to flocculate and settle very easily and quickly. It also increases the yield of DNA in a way, because the provision of lowered temperature may reduce enzymatic activity of DNA degrading enzymes and protect the DNA that is isolated from this step on.
Charged molecules are generally stabilised by ionic solvents and uncharged molecules are more soluble in uncharged organic solvents. DNA is highly charged and in the presence of 35% isopropanol and 0.5M salt the dna will be precipitated along with a little salt. Ethanol does the same thing but tends to precipitate less salt but also less of the DNA. The purpose of the alcohols is to provide a slightly organic environment that precipitates the dna while also having a hydroxyl group that allows most of the salt to stay in solution
Agreed with Paul, though its recommended to use RT Isopropanol. cold Isopropanol may increase precipitation of salt (white precipitate at the bottom of the tube).
The use of chilled IPA increases the rate of precipitation of DNA and allows it to flocculate and settle very easily and quickly. It also increases the yield of DNA in a way, because the provision of lowered temperature may reduce enzymatic activity of DNA degrading enzymes and protect the DNA that is isolated from this step on.
Sara Mehrabi, Hasanka Madubashetha , Paul Rutland thanks for valuable answers.
Hello
Using chilled alcohol increases the precipitation rate of the DNA.
Good Luck
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