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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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(A) Schematic drawing of a LAPS device to monitor beating of cardiomyocytes immobilized on the semiconductor layer. The light pointer is focused above the LAPS, and illuminates vertically above the desired cells. Depending on the bias voltage, photocurrent of the LAPS is monitored by the detection system through peripheral circuit; (B) Effect of heavy metals on the spontaneous beating amplitude of the cardiomyocytes recorded by LAPS (mean ± S.E.M.; n = 7). Reprinted from [136] with permission from Elsevier.
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biosensors-05-00241-f020: (A) Schematic drawing of a LAPS device to monitor beating of cardiomyocytes immobilized on the semiconductor layer. The light pointer is focused above the LAPS, and illuminates vertically above the desired cells. Depending on the bias voltage, photocurrent of the LAPS is monitored by the detection system through peripheral circuit; (B) Effect of heavy metals on the spontaneous beating amplitude of the cardiomyocytes recorded by LAPS (mean ± S.E.M.; n = 7). Reprinted from [136] with permission from Elsevier.

Mentions: Liu et al. [136] described a novel biosensor for monitoring the changes in electrophysiological activity upon heavy metal exposure. They developed a light-addressable potentiometric sensor (LAPS) [137,138] based on cardiomyocytes immobilized on a semiconductor. Upon illumination of the semiconductor through the cardiomyocytes, the latter produce an ionic current and also change their shape, which lead to a fluctuation of the photocurrent (Figure 20A). After being exposed to different heavy metal ions (Hg2+, Pb2+, Cd2+, Fe3+, Cu2+, Zn2+), cardiomyocytes demonstrated characteristic changes in terms of beating frequency, amplitude and duration under the different toxic effects of ions, in less than 15 min. The limit of detection depends on the metal, but sits between 1 μM and 10 μM (Figure 20B). This technique paves the way to new bio-analytical methods, instrumentation and cell-based assays for in vitro toxicity screening.


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

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

(A) Schematic drawing of a LAPS device to monitor beating of cardiomyocytes immobilized on the semiconductor layer. The light pointer is focused above the LAPS, and illuminates vertically above the desired cells. Depending on the bias voltage, photocurrent of the LAPS is monitored by the detection system through peripheral circuit; (B) Effect of heavy metals on the spontaneous beating amplitude of the cardiomyocytes recorded by LAPS (mean ± S.E.M.; n = 7). Reprinted from [136] with permission from Elsevier.
© Copyright Policy
Related In: Results  -  Collection

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

biosensors-05-00241-f020: (A) Schematic drawing of a LAPS device to monitor beating of cardiomyocytes immobilized on the semiconductor layer. The light pointer is focused above the LAPS, and illuminates vertically above the desired cells. Depending on the bias voltage, photocurrent of the LAPS is monitored by the detection system through peripheral circuit; (B) Effect of heavy metals on the spontaneous beating amplitude of the cardiomyocytes recorded by LAPS (mean ± S.E.M.; n = 7). Reprinted from [136] with permission from Elsevier.
Mentions: Liu et al. [136] described a novel biosensor for monitoring the changes in electrophysiological activity upon heavy metal exposure. They developed a light-addressable potentiometric sensor (LAPS) [137,138] based on cardiomyocytes immobilized on a semiconductor. Upon illumination of the semiconductor through the cardiomyocytes, the latter produce an ionic current and also change their shape, which lead to a fluctuation of the photocurrent (Figure 20A). After being exposed to different heavy metal ions (Hg2+, Pb2+, Cd2+, Fe3+, Cu2+, Zn2+), cardiomyocytes demonstrated characteristic changes in terms of beating frequency, amplitude and duration under the different toxic effects of ions, in less than 15 min. The limit of detection depends on the metal, but sits between 1 μM and 10 μM (Figure 20B). This technique paves the way to new bio-analytical methods, instrumentation and cell-based assays for in vitro toxicity screening.

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
Related in: MedlinePlus