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.

Show MeSH
Anodic Stripping Voltammetry (ASV) principle.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493548&req=5

biosensors-05-00241-f001: Anodic Stripping Voltammetry (ASV) principle.

Mentions: Stripping voltammetry comprises a group of various techniques including Anodic Stripping Voltammetry, Cathodic Stripping Voltammetry (CSV) and Adsorptive Stripping Voltammetry (AdSV). It is an ultrasensitive detection technique based on electrochemical measurements similar to polarography. Stripping voltammetry is a two-step technique that allows simultaneous detection of various inorganic and organic species in the sub-nanomolar range. The first step consists of the electrolytic deposition of a chemical species onto an inert electrode surface at a constant potential. This preconcentration step explains the remarkable sensitivity of the technique. It can involve either an anodic or cathodic process. However, the most common use of stripping voltammetry involves a cathodic process for deposition in which the metal ionic species are reduced from the solution to the electrode surface. The second step consists of the application of a voltage scan to the electrode. At a specific potential, it causes the stripping of a specific species accumulated onto the electrode surface as amalgam or thin films, into the solution. The resulting faradic current is proportional to the concentration of the chemical species (Figure 1).


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

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

Anodic Stripping Voltammetry (ASV) principle.
© Copyright Policy
Related In: Results  -  Collection

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

biosensors-05-00241-f001: Anodic Stripping Voltammetry (ASV) principle.
Mentions: Stripping voltammetry comprises a group of various techniques including Anodic Stripping Voltammetry, Cathodic Stripping Voltammetry (CSV) and Adsorptive Stripping Voltammetry (AdSV). It is an ultrasensitive detection technique based on electrochemical measurements similar to polarography. Stripping voltammetry is a two-step technique that allows simultaneous detection of various inorganic and organic species in the sub-nanomolar range. The first step consists of the electrolytic deposition of a chemical species onto an inert electrode surface at a constant potential. This preconcentration step explains the remarkable sensitivity of the technique. It can involve either an anodic or cathodic process. However, the most common use of stripping voltammetry involves a cathodic process for deposition in which the metal ionic species are reduced from the solution to the electrode surface. The second step consists of the application of a voltage scan to the electrode. At a specific potential, it causes the stripping of a specific species accumulated onto the electrode surface as amalgam or thin films, into the solution. The resulting faradic current is proportional to the concentration of the chemical species (Figure 1).

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