The experiment of precipitating DNA can be applied to isolate DNA.
Operation method
ethanol precipitation
Principle
DNA solution is the stable existence of DNA in a hydrated state, when adding ethanol, ethanol will take away the water molecules around the DNA, so that the DNA loses water and is easy to polymerize. General experiments, is to add 2 times the volume of anhydrous ethanol and DNA mixed, the final content of ethanol accounted for about 67%. Thus, 95% ethanol can also be used to replace the slack water ethanol (because the price of anhydrous ethanol is far more expensive than 95% ethanol). However, the addition of 95% ethanol increases the total volume, and DNA is solubilized to a certain extent in the solution, thus increasing the loss of DNA, especially when multiple ethanol precipitations are used, which affects the yield. Instead of anhydrous ethanol, 95% ethanol can be used for the initial DNA precipitation, and anhydrous ethanol should be used for the final precipitation step. DNA can also be selectively precipitated with 0.6 times the volume of isopropanol. 15-30 minutes at room temperature is usually sufficient.
Materials and Instruments
DNA Move 1. Determine the concentration of the sample to be digested and select the appropriate restriction endonuclease and Buffer before digestion.2. Add the following components to the centrifuge tube:10xBuffer 1ulSample to be cut xulEnzyme 0.5-1ul ______________________ Caveat Removal of the supernatant needs to be done slowly so as not to dislodge the DNA sample. Common Problems Ethanol can be miscible with water at any ratio, and ethanol does not have any chemical reaction with nucleic acids, so it is safe for DNA, and therefore it is an ideal precipitant. For more product details, please visit Aladdin Scientific website.
Sodium acetate Ethanol
EP tube Low temperature centrifuge Pipette -70 degrees refrigerator
Add water to make up 10ul3. Mix the sample and centrifuge briefly to allow the sample to settle to the bottom of the tube.4. Place the tube at 37°C for 1-3hr, or longer if the sample to be digested is a PCR product.5. The uncut plasmid is used as a control, and the results are analyzed by agarose electrophoresis.Note: When the digested sample is used for recovery rather than identification, the reaction volume can be increased proportionally. For double digestion, use Buffer with higher activity or Universal Buffer, but be careful not to have a star reaction.