Affinity chromatography of acetylcholinesterase from Electrophorus electricus electroplax. Investigations on 9-aminoalkylacridine affinity ligands.

The neural enzyme 11-S acetylcholinesterase (E.C. 3.1.1.7) was purified by affinity chromatography from a trypsin digest of Electrophorus electricus electric organ. Unquaternized affinity ligands were reported which were comparable in efficacy to the routinely employed "quaternized acridine MAC ligand". A study was made of the quaternization reactions of various 9-aminoalkylacridines and 9-aminoacridine along with their relative binding affinities to acetylcholinesterase. Ease of synthesis in conjunction with the column performance of these unquaternized 9-aminoalkylacridine compounds made them the preferred affinity ligand in acetylcholinesterase chromatography. A new carbodiimide synthetic route for these unquaternized ligands was described.