Luminol Chemiluminescence in Unbuffered Solutions with a Cobalt(II)-Ethanolamine Complex Immobilized on Resin as Catalyst and Its Application to Analysis

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• 作者：Jin-Ming Lin ; Xiaoquan Shan ; Soichi Hanaoka ; and Masaaki Yamada
• 刊名：Analytical Chemistry
• 出版年：2001
• 出版时间：November 1, 2001
• 年：2001
• 卷：73
• 期：21
• 页码：5043 - 5051
• 全文大小：179K
• 年卷期：v.73,no.21(November 1, 2001)
• ISSN：1520-6882

文摘

Using a heterogeneous catalyst, Co(II)-ethanolaminecomplex sorbed on Dowex-50W resin, the chemiluminescence (CL) of luminol in unbuffered or weakly acidicsolution was studied in the presence of H₂O₂. Themaximum luminol CL wavelength at pH 5.7 was 448 nm,23 nm longer than that in a basic solution (pH 10.5).Three different ligands, mono-, di-, and triethanolamine,and six transition metal ions, Co(II), Cu(II), Ni(II), Mn(II), Fe(II), and Fe(III) were compared by CL measurements. The CL intensity decreased in the order mono- >di- > triethanolamine and Co(II) > Cu(II) > Ni(II) > Fe(III) > Mn(II) > Fe(II). This heterogeneous CL systemwas developed as H₂O₂ and glucose flow-through sensors.Detection limits (S/N = 3) of H₂O₂ and glucose usingDowex-50W-X4-Co(II)-monoethanolamine as catalystare 1 × 10^-7 M and 1 × 10^-6 M, respectively. On thebasis of the studies of the CL, fluorescence, UV-vis andESCA spectra and the effect of dissolved oxygen in luminolsolution, a mechanism for CL emission in unbufferedsolution was considered as the formation of a superoxideradical ion during the decomposition of H₂O₂ catalyzedby the Co(II)-ethanolamine immobilized resin. Then thesuperoxide radical ion acted on luminol and the CL wasemitted. The applications of the proposed method todetermine H₂O₂ in rainwater without any special pretreatment and glucose in human urine and orange juicesamples give satisfactory results.