title: Simultaneous detection and removal of radioisotopes with modified alginate beads containing an azo-based probe using RGB coordinates.
abstract: We prepared alginate beads that were modified with an azo-based probe molecule to monitor simultaneously the removal (by alginate) and probing (by the azo-probe molecule) of radioisotopes such as cobalt, strontium, and cesium ions. As an azo-probe molecule, Basic Orange 2 (BO2) was immobilized to the alginate bead. The BO2 in aqueous solution exhibited a slight red shift in absorption with a change in color from orange to dark orange upon addition of cobalt and strontium ions. In contrast, the color of BO2 did not change upon exposure to cesium ions. Thus, the covalently embedded BO2 in alginate beads could adsorb cobalt and strontium ions resulting in recognizable color change of the beads, which was induced by the formation of a complex between BO2 and metal ions. The color changes of the beads in the presence of metal ions were determined quantitatively using RGB color coordinate values. In addition to effectively removing metal ions, the colorimetric coordinate method provides a convenient and simple sensing technique for naked-eye metal ion detection.
authors.affiliation: Organic and Optoelectronic Materials Laboratory, Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Ara
authors.initials: A
authors.lastname: Jo
authors.affiliation: Organic and Optoelectronic Materials Laboratory, Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Geunseok
authors.initials: G
authors.lastname: Jang
authors.affiliation: Organic and Optoelectronic Materials Laboratory, Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Ho
authors.initials: H
authors.lastname: Namgung
authors.affiliation: Organic and Optoelectronic Materials Laboratory, Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Choongho
authors.initials: C
authors.lastname: Kim
authors.affiliation: Organic and Optoelectronic Materials Laboratory, Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Daigeun
authors.initials: D
authors.lastname: Kim
authors.affiliation: Organic and Optoelectronic Materials Laboratory, Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Yujun
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Organic and Optoelectronic Materials Laboratory, Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Jongho
authors.initials: J
authors.lastname: Kim
authors.affiliation: Organic and Optoelectronic Materials Laboratory, Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764, South Korea. Electronic address: tslee@cnu.ac.kr.
authors.forename: Taek Seung
authors.initials: TS
authors.lastname: Lee
keywords: Alginate bead; Azo probe; Cesium; Cobalt; RGB color coordinate; Strontium