Analytical Sciences

Abstract − Analytical Sciences, 25(1), 51 (2009).

Automated Pretreatment System for the Speciation of Cr(III) and Cr(VI) Using Dual Mini-Columns Packed with Newly Synthesized Chitosan Resin and ME-03 Resin
Yoshiaki FURUSHO,*1 Akhmad SABARUDIN,*2 Lukman HAKIM,*3 Koji OSHITA,*4 Mitsuko OSHIMA,*3 and Shoji MOTOMIZU*3
*1 GL Sciences Inc., 6-22-1 Nishi-shinjuku, Shinjuku, Tokyo 163-1130, Japan
*2 Department of Chemistry, Faculty of Science, Brawijaya University, Jl Veteran, Malang 65145, Indonesia
*3 Department of Chemistry, Faculty of Science, Okayama University, 3-1-1 Tsushimanaka, Okayama 700-8530, Japan
*4 Department of International Conservation Studies for Cultural Properties, Faculty of Cultural Properties, Kibi International University, 8 Iga-machi, Takahashi, Okayama 716-8508, Japan
Chitosan resin possessing the 4-hydroxyphthalic acid moiety (CCTS-HPA resin) was synthesized. This resin could adsorb chromium(VI) at pH 3 to 5, whereas chromium(III) could not be retained in the acidic region. The CCTS-HPA resin was used for collecting chromium(VI), and ME-03 resin was used for collecting chromium(III) before their measurement by ICP-AES measurement. Both resins were packed in mini-columns and installed serially in a laboratory-assembled automated pretreatment system (Auto-Pret System). The system provides a highly sensitive and fully automated procedure for the speciation of chromium(III) and chromium(VI). The proposed system was successfully applied to speciation of chromium(III) and chromium(VI) using 5 ml of water samples. The detection limits (S/N = 3) of chromium(III) and chromium(VI) were 0.06 and 0.04 µg l-1, respectively, along with an analysis time of 7 min 45 s for both chromium species. The lowest determinable concentrations for both chromium species were about 0.5 µg l-1, whichwas enough for the speciation of chromium in water samples.