Solution III


Solution III for the plasmid DNA purification process is

5M Potassium Acetate 60.0 ml      See Mixing Solutions: Mystery Solved
Glacial Acetic Acic  11.5 ml      CAUTION! See Glacial Acetic Acid Safety Notes 
Distilled water      28.5 ml

The resulting solution is 3 M with respect to potassium and 5 M with respect to acetate.

Potassium Acetate is C_2H_3K_2, with a molar mass of 98.15 gr/mole. Make 5M Potassium Acetate (100 ml is good), and autoclave on liquid cycle at 121 degrees C for 15 min. It is also a good idea to autoclave some water and a GLASS storage bottle that can hold at least 150ml.

After autoclaving, measure the 5 M Potassium Acetate and Distilled Water into the clean, autoclaved glass storage bottle rather than a beaker.

Before adding the glacial acetic acid read the Team:Baltimore/Working under the Hood Page.

Work under the Ventilation Hood and wear coat, googles, and double gloves, carefully open the glacial acetic acid bottle. Glacial acetic acid is often stored in a large bottle with a small neck, and always stored cold. Use a disposable pipette and a pipette liquid drawer (green thing with the white gear) to measure the 11.5 ml of acetic acid and add to the bottle (which is now also under the hood) containing your Potassium Acetate and water solution. You now have Solution III. Store in the -4 degree C freezer, well-labeled with a cautionary note stating the contents include glacial acetic acid.