Determination of monovalent inorganic anions in high-ionic-strength samples by electrostatic ion chromatography with suppressed conductometric detection.
A new ion chromatographic (IC) system has been established by using micelles of 3-(N,N-dimethylmyristylammonio)propanesulfonate (Zwittergent 3-14) loaded onto a reversed-phase packed column as the separation column with an electronic rotary switching valve packed-bed suppressor for conductometric detection of inorganic anions. An aqueous H3BO3-Na2B4O7 solution has been demonstrated to be the most desirable eluent for this IC system. The relationship between retention time and the concentration of the borate eluent was determined for a series of model anionic analytes and this relationship was found to be opposite to that exhibited in a conventional anion-exchange IC system. The rapid elution and complete separation of monovalent inorganic anions were obtained by initially using a high-concentration borate solution as the eluent for a short-period, and then switching to a lower-concentration borate eluent to complete the separation. Detection limits for nitrite, bromide, nitrate, and chlorate were 0.85, 0.88, 0.95 and 4.8 microM, respectively, when a 7.0 mM Na2B4O7 eluent was used. Moreover, the ability to directly detect these monovalent anions in samples containing high concentrations of sulfate and/or chloride ions provided a major advantage of this approach.
Hu
Wenzhi
W
Laboratory of Bio-Functional Chemistry, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan. hu@ees.hokudai.ac.jp
Haddad
Paul R
PR
Tanaka
Kazuhiko
K
Sato
Shinji
S
Mori
Masanobu
M
Xu
Qun
Q
Ikedo
Mikaru
M
Tanaka
Shunitz
S
D000838:Anions / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods*; D007287:Inorganic Chemicals / Q000032:analysis*; D009994:Osmolar Concentration; D012680:Sensitivity and Specificity; D055672:Static Electricity
D000838:Anions; D007287:Inorganic Chemicals