Complexation of Heavy Metals by Phytochelatins: Voltammetric Study of the Binding of Cd2+ and Zn2+ Ions by the Phytochelatin (
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- 作者：Boris H. Cruz ; José ; Manuel Dí ; az-Cruz ; Cristina Ariñ ; o ; and Miquel Esteban
- 刊名：Environmental Science & Technology
- 出版年：2005
- 出版时间：February 1, 2005
- 年：2005
- 卷：39
- 期：3
- 页码：778 - 786
- 全文大小：438K
- 年卷期：v.39,no.3(February 1, 2005)
- ISSN：1520-5851
文摘
The complexation of Cd2+, Zn2+, and both together withthe phytochelatin (
-Glu-Cys)3Gly is studied by differentialpulse polarography, and data are analyzed by multivariatecurve resolution by alternating least squares (MCR-ALS). MCR-ALS yields the respective unitary voltammograms andconcentration profiles of the resolved components, whichcontain information on the relative stabilities andstoichiometries of the formed complexes. The analysis ofthese results shows, for the Cd2+/(-Glu-Cys)3Gly system, thepresence of different kinds of bound Cd2+. For the Zn2+/(-Glu-Cys)3Gly system, the poor definition of the reductionsignals of the complexes prevents a clear discriminationamong differently bound Zn2+ ions. A tentative complexation/electrochemical model is proposed for when both metalions, Cd2+ and Zn2+, compete toward complexation, andsome of the corresponding equilibrium constants areestimated.
-Glu-Cys)3Gly is studied by differentialpulse polarography, and data are analyzed by multivariatecurve resolution by alternating least squares (MCR-ALS). MCR-ALS yields the respective unitary voltammograms andconcentration profiles of the resolved components, whichcontain information on the relative stabilities andstoichiometries of the formed complexes. The analysis ofthese results shows, for the Cd2+/(-Glu-Cys)3Gly system, thepresence of different kinds of bound Cd2+. For the Zn2+/(-Glu-Cys)3Gly system, the poor definition of the reductionsignals of the complexes prevents a clear discriminationamong differently bound Zn2+ ions. A tentative complexation/electrochemical model is proposed for when both metalions, Cd2+ and Zn2+, compete toward complexation, andsome of the corresponding equilibrium constants areestimated.