Influence of acidic eluent for retention behaviors of common anions and cations by ion-exclusion/cation-exchange chromatography on a weakly acidic cation-exchange resin in the H+ -form.
Influence of acidic eluent on retention behaviors of common anions and cations by ion-exclusion/cation-exchange chromatography (ion-exclusion/CEC) were investigated on a weakly acidic cation-exchange resin in the H(+)-form with conductivity. Sensitivities of analyte ions, especially weak acid anions (F(-) and HCOO(-)), were affected with degree of background conductivity level with pK(a1) (first dissociation constant) of acid in eluent. The retention behaviors of anions and cations were related to that of elution dip induced after eluting acid to separation column and injecting analyte sample. These results were largely dependent on the natures of acid as eluent. Through this study, succinic acid as the eluent was suitable for simultaneous separation of strong acid anions (SO(4)(2-), Cl(-), NO(3)(-) and I(-)), weak acid anions (F(-), HCOO(-) and CH(3)COO(-)), and cations (Na(+), K(+), NH(4)(+), Mg(2+) and Ca(2+)). The separation was achieved in 20 min under the optimum eluent condition, 20 mM succinic acid/2 mM 18-crown-6. Detection limits at S/N=3 ranged from 0.10 to 0.51 microM for strong acid anions, 0.20 to 5.04 microM for weak acid anions and 0.75 to 1.72 microM for cations. The relative standard deviations of peak areas in the repeated chromatographic runs (n=10) were in the range of 1.1-2.9% for anions and 1.8-4.5% for cations. This method was successfully applied to hot spring water containing strong acid anions, weak acid anions and cations, with satisfactory results.
Faculty of Engineering, Gunma University, Kiryu, Gunma 376-8515, Japan. m_mori@chem.chem-u.ac.jp
Masanobu
M
Mori
Kazuhiko
K
Tanaka
Tatsuya
T
Satori
Mikaru
M
Ikedo
Wenzhi
W
Hu
Hideyuki
H
Itabashi
D000838:Anions / Q000032:analysis*; D002411:Cation Exchange Resins / Q000737:chemistry*; D002412:Cations / Q000032:analysis*; D002850:Chromatography, Gel / Q000379:methods*; D002852:Chromatography, Ion Exchange / Q000379:methods*; D043844:Crown Ethers / Q000737:chemistry; D045482:Hot Springs / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D011522:Protons; D015203:Reproducibility of Results; D019802:Succinic Acid / Q000737:chemistry
D000838:Anions; D002411:Cation Exchange Resins; D002412:Cations; D043844:Crown Ethers; D011522:Protons; C015762:18-crown-6; D019802:Succinic Acid