Limits...
Modified electrodes used for electrochemical detection of metal ions in environmental analysis.

March G, Nguyen TD, Piro B - Biosensors (Basel) (2015)

Bottom Line: Many efforts have been made to develop sensors for monitoring heavy metals in the environment.The first part of this review will be dedicated to stripping voltammetry techniques, on unmodified electrodes (mercury, bismuth or noble metals in the bulk form), or electrodes modified at their surface by nanoparticles, nanostructures (CNT, graphene) or other innovative materials such as boron-doped diamond.Special attention will be paid to strategies using biomolecules (DNA, peptide or proteins), enzymes or whole cells.

View Article: PubMed Central - PubMed

Affiliation: Klearia, route de Nozay, Marcoussis 91460, France. gregory.march@free.fr.

ABSTRACT
Heavy metal pollution is one of the most serious environmental problems, and regulations are becoming stricter. Many efforts have been made to develop sensors for monitoring heavy metals in the environment. This review aims at presenting the different label-free strategies used to develop electrochemical sensors for the detection of heavy metals such as lead, cadmium, mercury, arsenic etc. The first part of this review will be dedicated to stripping voltammetry techniques, on unmodified electrodes (mercury, bismuth or noble metals in the bulk form), or electrodes modified at their surface by nanoparticles, nanostructures (CNT, graphene) or other innovative materials such as boron-doped diamond. The second part will be dedicated to chemically modified electrodes especially those with conducting polymers. The last part of this review will focus on bio-modified electrodes. Special attention will be paid to strategies using biomolecules (DNA, peptide or proteins), enzymes or whole cells.

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Comparative voltammograms of a solution containing 20 ppb each of Pb(II), Cd(II) and Zn(II) in 0.1 M acetate buffer (pH 4.5) on in situ plated BFE and MFE on a glassy carbon support. Reprinted from [37] with permission from Elsevier.
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biosensors-05-00241-f003: Comparative voltammograms of a solution containing 20 ppb each of Pb(II), Cd(II) and Zn(II) in 0.1 M acetate buffer (pH 4.5) on in situ plated BFE and MFE on a glassy carbon support. Reprinted from [37] with permission from Elsevier.

Mentions: The main disadvantage of BFEs compared to MFEs is their lower potential window, particularly a more negative anodic limit due to the fact that bismuth is more easily oxidized than mercury. However, the cathodic limit potential is almost the same as MFEs. The pH of the sample solution strongly affects the useful potential window of BFEs. As expected, the most cathodic potential limit was achieved in basic media whereas the most anodic potential limit was achieved in very acidic media. Table 2 shows potential ranges of BFEs at different pH values [37], and Figure 3 shows an example for simultaneous Pb2+, Zn2+ and Cd2+ determination.


Modified electrodes used for electrochemical detection of metal ions in environmental analysis.

March G, Nguyen TD, Piro B - Biosensors (Basel) (2015)

Comparative voltammograms of a solution containing 20 ppb each of Pb(II), Cd(II) and Zn(II) in 0.1 M acetate buffer (pH 4.5) on in situ plated BFE and MFE on a glassy carbon support. Reprinted from [37] with permission from Elsevier.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493548&req=5

biosensors-05-00241-f003: Comparative voltammograms of a solution containing 20 ppb each of Pb(II), Cd(II) and Zn(II) in 0.1 M acetate buffer (pH 4.5) on in situ plated BFE and MFE on a glassy carbon support. Reprinted from [37] with permission from Elsevier.
Mentions: The main disadvantage of BFEs compared to MFEs is their lower potential window, particularly a more negative anodic limit due to the fact that bismuth is more easily oxidized than mercury. However, the cathodic limit potential is almost the same as MFEs. The pH of the sample solution strongly affects the useful potential window of BFEs. As expected, the most cathodic potential limit was achieved in basic media whereas the most anodic potential limit was achieved in very acidic media. Table 2 shows potential ranges of BFEs at different pH values [37], and Figure 3 shows an example for simultaneous Pb2+, Zn2+ and Cd2+ determination.

Bottom Line: Many efforts have been made to develop sensors for monitoring heavy metals in the environment.The first part of this review will be dedicated to stripping voltammetry techniques, on unmodified electrodes (mercury, bismuth or noble metals in the bulk form), or electrodes modified at their surface by nanoparticles, nanostructures (CNT, graphene) or other innovative materials such as boron-doped diamond.Special attention will be paid to strategies using biomolecules (DNA, peptide or proteins), enzymes or whole cells.

View Article: PubMed Central - PubMed

Affiliation: Klearia, route de Nozay, Marcoussis 91460, France. gregory.march@free.fr.

ABSTRACT
Heavy metal pollution is one of the most serious environmental problems, and regulations are becoming stricter. Many efforts have been made to develop sensors for monitoring heavy metals in the environment. This review aims at presenting the different label-free strategies used to develop electrochemical sensors for the detection of heavy metals such as lead, cadmium, mercury, arsenic etc. The first part of this review will be dedicated to stripping voltammetry techniques, on unmodified electrodes (mercury, bismuth or noble metals in the bulk form), or electrodes modified at their surface by nanoparticles, nanostructures (CNT, graphene) or other innovative materials such as boron-doped diamond. The second part will be dedicated to chemically modified electrodes especially those with conducting polymers. The last part of this review will focus on bio-modified electrodes. Special attention will be paid to strategies using biomolecules (DNA, peptide or proteins), enzymes or whole cells.

Show MeSH