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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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FE-SEM images of (A) PDAN; (B) pure CNT and (C) PDAN/CNT. Reprinted from [99] with permission from Elsevier.
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biosensors-05-00241-f010: FE-SEM images of (A) PDAN; (B) pure CNT and (C) PDAN/CNT. Reprinted from [99] with permission from Elsevier.

Mentions: Carbon nanotubes (CNTs) have a large surface-to-volume ratio, good conductivity and strong adsorption ability that were proved to be useful for improving the sensitivity of sensors in general, and ions sensors in particular. Applying these properties, Wang et al. [97] used PANi-modified CNTs to detect Pb2+ by SWASV and found that CNT:PANI-coated electrodes had better performances than bare GCE. Other publications demonstrated that CNTs functionalized with aromatic amines are efficient for HMs adsorption. For example, Salmanipour et al. [98] functionalized GC electrodes with a mixture of multi-walled carbon nanotubes (MWCNTs) and 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and detected Pb2+ by ASV in a range from 1 to 115 μg L−1. CPs/CNTs nanocomposites may also be made electrochemically. For example, Nguyen et al. [99] electropolymerized a mixture of PDAN and CNT on interdigitated arrays (Figure 10).


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

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

FE-SEM images of (A) PDAN; (B) pure CNT and (C) PDAN/CNT. Reprinted from [99] with permission from Elsevier.
© Copyright Policy
Related In: Results  -  Collection

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

biosensors-05-00241-f010: FE-SEM images of (A) PDAN; (B) pure CNT and (C) PDAN/CNT. Reprinted from [99] with permission from Elsevier.
Mentions: Carbon nanotubes (CNTs) have a large surface-to-volume ratio, good conductivity and strong adsorption ability that were proved to be useful for improving the sensitivity of sensors in general, and ions sensors in particular. Applying these properties, Wang et al. [97] used PANi-modified CNTs to detect Pb2+ by SWASV and found that CNT:PANI-coated electrodes had better performances than bare GCE. Other publications demonstrated that CNTs functionalized with aromatic amines are efficient for HMs adsorption. For example, Salmanipour et al. [98] functionalized GC electrodes with a mixture of multi-walled carbon nanotubes (MWCNTs) and 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and detected Pb2+ by ASV in a range from 1 to 115 μg L−1. CPs/CNTs nanocomposites may also be made electrochemically. For example, Nguyen et al. [99] electropolymerized a mixture of PDAN and CNT on interdigitated arrays (Figure 10).

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