Nucleic Acids by the Orcinol Reaction

Dissolve 13.5 g ferric ammonium sulfate and 20.0 g orcinol in 500 ml glass-distilled water. This reagent may be stored at 4°C for short periods. If the reagent begins to darken, it should be discarded. 

0 ml of the reagent prepared in step 2-39 to a solution composed of 85 ml concentrated HCl and 10 ml glass-distilled water (final total volume should be 100 ml). 

Add an appropriate amount of distilled water to each tube to give a final volume of 1.0 ml. 

0 ml of the solution prepared in step 2-40 to each tube and mix the solution thoroughly by vortexing. 

Place the covered tubes in a rack and place the rack in a pan of vigorously boiling water for 20 minutes. This should be done as soon as possible after step 2-43. 

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