Potentiometric studies of binary and ternary complexes of amoxycillin.

The formation equilibria for the binary complexes of copper(II), nickel(II), cobalt(II) and zinc(II) with amoxycillin (Amx) and for the ternary complexes M(Arm)(Amx), where Arm refers to aromatic amines, namely 2,2'-dipyridyl or 1,10-phenanthroline, were investigated by a potentiometric technique. The protonation constants of amoxycillin and conditional stability constants of the formed complexes were determined at 25 degrees (=0.1M NaNO(3)). Probable mode of chelation with amoxycillin is discussed.