After removing the protein precipitate, add anhydrous ethanol to precipitate the plasmid, centrifuge to remove the supernatant, add 70% ethanol to clean the DNA precipitate, and wash it twice. Finally, the DNA precipitate should be dissolved in te or ddH2O.
Extended data:
1. Measure the volume of DNA solution, accurately add solid CsCl according to the dosage of 1g/ml, and heat the solution to 30℃ to help dissolve. Stir the solution gently until the salt dissolves.
2. Add 0.8ml ethidium bromide solution (10mg/ml dissolved in water) to every 10mlDNA solution; Immediately mix the ethidium bromide solution (floating on the surface) with the DNA-cesium chloride solution. The final density of the solution should be 1.55g/ml (refractive index of the solution is 1.3860), and the concentration of ethidium bromide is about 740μg/ml. The storage solution of ethidium bromide should be stored in a light-proof container (such as a bottle completely wrapped with tin foil) and stored at room temperature.
Baidu encyclopedia-plasmid DNA purification