Abstract Potentiometric and conductometric studies of binary and ternary complexes of sulphamethoxazole (SMZ) and glycine (Gly) with metal ions; Fe(III), Pb(II), Co(II), Al(III), La(III), Sr(II), Cr(III), Th(IV), Ti(II) and Zr(IV). In 0.1 M NaClO4 and 25 % (v/v) ethanol–water mixture, stability constant of metal ions complexes with SMZ have been determined potentiometrically. The ionic strength effect on the formed complexes stability was studied. The stoichiometries of these complexes were determined conductometrically and indicated that the formation of 1: 1, 1: 2 and/or 1: 3 (metal: ligand) complexes. Also, the species distribution diagrams of SMZ and its metal ion complexes were reported. For ternary complex; M: SMZ: Gly = 1: 1: 1, the protonation constants were calculated. The order of stability of both binary and ternary complexes was examined.
Keywords Sulfamethoxazole, Glycine, Potentiometry, Conductometry, Stability Constants, Distribution Diagrams.