Aluminon, the triammonium salt of aurintricarboxylic acid, is a dye often used to detect the presence of the aluminium ion in an aqueous solution. Aluminon forms a red complex salt in combination with Al3+.
Aurintricarboxylic acid readily polymerizes in aqueous solution, forming a stable free radical that inhibits protein-nucleic acid interactions. It is a potent inhibitor of ribonuclease and topoisomerase II by preventing the binding of the nucleic acid to the enzyme.