4-Aminobenzoic Acid Solution

4-Aminobenzoic Acid Solution Dissolve 1 g of 4-aminobenzoic acid in a mixture of 18 mL of anhydrous acetic acid, 20 mL of water and 1 mL of orthophosphoric acid. Immediately before use, mix 2 volumes of the solution with 3 volumes of acetone.