Separation of 1,10-phenanthroline complexes of iron(II), nickel(II), and ruthenium(II) by reversed-phase, paired-ion chromatography

Separation of cationic metal chelates of 1,10-phenanthroline by liquid chromatography

“…All three peaks are resolved and well separated from a peak due to the ligand, Hphen+, and a minor peak believed to be a bis(l,10phenanthroline)ruthenium(II) species. This minor impurity was observed previously (1) and found to have essentially the same UV spectrum and fluorescence characteristics as the Ru(phen)32+ species.…”

“…It should be noted, however, that the elution order is different-Ni, Ru, and Fe for the Partisil column and Fe, Ni, and Ru for the PRP-1 column. The elution order of the inert iron, nickel, and ruthenium complexes appears to be characteristic of the particular column and does not change with composition of the mobile phase as previously suggested as a possibility (1) although the retention volumes of the labile complexes do vary with ligand concentration. The mechanism by which metal chelates are adsorbed on resins of this type and the effect of the coanion have been addressed by Lundgren and Schilt (5).…”

“…The separation of the 1,10-phenanthroline chelates Ni-(phen)32+ and Ru(phen)32+ from Fe(phen)32+ but not from each other by ion-pair, high-performance liquid chromatography has been previously reported (1). The separation of all three of the above chelates from each other and the extension of this technique to the separation of the labile 1,10phenanthroline chelates of Zn(II), Cd(II), Co(II), and Cu(II) on µ-Partisil-SCX (cation exchange) and the Hamilton-PRP-1 (polystyrene-divinylbenzene bead) columns with the perchlorate ion as the pairing ion is reported in the present paper.…”

“…All other chemicals were reagent grade except the LiC104 which was prepared by treatment of ultrapure Li2C03 with perchloric acid and recrystallization of the LiC104 from water. The preparation of the solid tris(l,10-phenanthroline) chelates as the iodide salts was described previously (1). Solutions of the labile metal chelates were prepared by dissolving appropriate amounts of the metal sulfates in water or the mobile phase and adding a small excess of 1,10-phenanthroline (1).…”

Capillary electrophoretic separation between Fe(II) and Ni(II) precomplexed with 1,10-phenanthroline in a high concentration buffer of n-butyric acid/n-butyrate and its application

“…Separation of Fe(II), Ni(II), and Ru(II) precomplexed with phen using perchlorate in acetonitrile-water by ionpair reversed-phase high-performance liquid chromatography (IP-RPLC) has been reported [7,8]. Also, separation of Fe(II) and Ni(II) precomplexed with bipyridine (bpy) using the thiocyanate ion in methanol-water by IP-RPLC has been reported [9].…”