Development of a microfluidics biosensor for agarose-bead immobilized Escherichia coli bioreporter cells for arsenite detection in aqueous samples.

Details

Serval ID
serval:BIB_97E35BF48444
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Development of a microfluidics biosensor for agarose-bead immobilized Escherichia coli bioreporter cells for arsenite detection in aqueous samples.
Journal
Lab On A Chip
Author(s)
Buffi N., Merulla D., Beutier J., Barbaud F., Beggah S., van Lintel H., Renaud P., van der Meer J.R.
ISSN
1473-0189 (Electronic)
ISSN-L
1473-0189
Publication state
Published
Issued date
2011
Volume
11
Number
14
Pages
2369-2377
Language
english
Abstract
Contamination with arsenic is a recurring problem in both industrialized and developing countries. Drinking water supplies for large populations can have concentrations much higher than the permissible levels (for most European countries and the United States, 10 μg As per L; elsewhere, 50 μg As per L). Arsenic analysis requires high-end instruments, which are largely unavailable in developing countries. Bioassays based on genetically engineered bacteria have been proposed as suitable alternatives but such tests would profit from better standardization and direct incorporation into sensing devices. The goal of this work was to develop and test microfluidic devices in which bacterial bioreporters could be embedded, exposed and reporter signals detected, as a further step towards a complete miniaturized bacterial biosensor. The signal element in the biosensor is a nonpathogenic laboratory strain of Escherichia coli, which produces a variant of the green fluorescent protein after contact to arsenite and arsenate. E. coli bioreporter cells were encapsulated in agarose beads and incorporated into a microfluidic device where they were captured in 500 × 500 μm(2) cages and exposed to aqueous samples containing arsenic. Cell-beads frozen at -20 °C in the microfluidic chip retained inducibility for up to a month and arsenic samples with 10 or 50 μg L(-1) could be reproducibly discriminated from the blank. In the 0-50 μg L(-1) range and with an exposure time of 200 minutes, the rate of signal increase was linearly proportional to the arsenic concentration. The time needed to reliably and reproducibly detect a concentration of 50 μg L(-1) was 75-120 minutes, and 120-180 minutes for a concentration of 10 μg L(-1).
Keywords
Arsenates/analysis, Arsenites/analysis, Biosensing Techniques/instrumentation, Biosensing Techniques/methods, Capsules/chemistry, Cells, Immobilized/drug effects, Cells, Immobilized/metabolism, Escherichia coli/drug effects, Escherichia coli/metabolism, Green Fluorescent Proteins/genetics, Green Fluorescent Proteins/metabolism, Microfluidic Analytical Techniques/instrumentation, Microfluidic Analytical Techniques/methods, Microscopy, Fluorescence, Sepharose/chemistry, Water Supply/analysis
Pubmed
Web of science
Create date
09/12/2011 8:29
Last modification date
20/08/2019 14:59
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