Solid phase biosensors for arsenic or cadmium composed of A trans factor and cis element complex.
Sensors (Basel)
; 11(11): 10063-73, 2011.
Article
em En
| MEDLINE
| ID: mdl-22346629
ABSTRACT
The presence of toxic metals in drinking water has hazardous effects on human health. This study was conducted to develop GFP-based-metal-binding biosensors for on-site assay of toxic metal ions. GFP-tagged ArsR and CadC proteins bound to a cis element, and lost the capability of binding to it in their As- and Cd-binding conformational states, respectively. Water samples containing toxic metals were incubated on a complex of GFP-tagged ArsR or CadC and cis element which was immobilized on a solid surface. Metal concentrations were quantified with fluorescence intensity of the metal-binding states released from the cis element. Fluorescence intensity obtained with the assay significantly increased with increasing concentrations of toxic metals. Detection limits of 1 µg/L for Cd(II) and 5 µg/L for As(III) in purified water and 10 µg/L for Cd(II) and As(III) in tap water and bottled mineral water were achieved by measurement with a battery-powered portable fluorometer after 15-min and 30-min incubation, respectively. A complex of freeze dried GFP-tagged ArsR or CadC binding to cis element was stable at 4 °C and responded to 5 µg/L As(III) or Cd(II). The solid phase biosensors are sensitive, less time-consuming, portable, and could offer a protocol for on-site evaluation of the toxic metals in drinking water.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligodesoxirribonucleotídeos
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Arsênio
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Proteínas de Bactérias
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Cádmio
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Técnicas Biossensoriais
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Transativadores
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Elementos Facilitadores Genéticos
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Proteínas de Escherichia coli
Idioma:
En
Revista:
Sensors (Basel)
Ano de publicação:
2011
Tipo de documento:
Article