Metal ion interaction with penicillins .8. Equilibrium study of mixed ligand complex formation of Co(II), Ni(II), Cu(II) and Zn(II) with ampicillin and some amino acids

Equilibrium study of complex formation of M(2+) ions (M = Co, Ni, Cu and Zn) with ampicillin (AH) and aminoacids (B), viz. glycinate, alpha-alaninate, beta-alaninate and aspartate in ternary systems in aqueous solution at 37 degrees C at a fixed ionic strength I = 0.1 mol dm(-3) (NaNO3) indicated the formation of mixed-ligand complexes of the types: M (A)(B), M(A-H)(B), M(A-H)(B)(OH), in addition to the binary M(A) and M(B) complexes. Stability of the mixed-ligand complexes were correlated with the modes of coordination of the ligands.