A test strip platform based on a whole-cell microbial biosensor for simultaneous on-site detection of total inorganic mercury pollutants in cosmetics without the need for predigestion

In this study, a test strip platform was developed based on a whole-cell microbial biosensor for the simultaneous detection of soluble and insoluble inorganic mercury pollutants in cosmetics without the need for predigestion. The genetic circuits with constitutively expressed MerR as sensor proteins and inducible red fluorescent protein (RFP) as the reporter were introduced into Escherichia coli to construct the mercury detection biosensor. The RFP fluorescence intensity of this biosensor showed a excellent linear relationship (R2 = 0.9848) with the Hg (II) concentration ranging from 50 nM to 10 μM in Luria-Bertani (LB) broth. Further research indicated that this biosensor could respond not only to Hg (II) ions but also to insoluble Hg2Cl2 and Hg2Cl2. The transcriptomic results confirmed the mercury conversion ability of the whole-cell biosensor from a gene expression perspective. This biosensor was embedded on filter paper to form a test strip, which could be used to determine whether the total inorganic mercury pollutants in cosmetics exceeded 1 mg/kg. Therefore, this strip provided a low cost, easy-to-use, and instrument-independent method for the detection of mercury pollution in cosmetics, while this study revealed the unique advantages of microbial biosensors in the automatic bioconversion of targets.Graphical abstract
Source: Biosensors and Bioelectronics - Category: Biotechnology Source Type: research

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Source: Enzyme and Microbial Technology - Category: Biotechnology Source Type: research
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Source: CNN.com - Health - Category: Consumer Health News Source Type: news
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Source: the Mail online | Health - Category: Consumer Health News Source Type: news
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Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
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Source: Wisconsin DHFS Press Releases - Category: Hospital Management Authors: Source Type: news
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Source: New Microbiologica - Category: Microbiology Tags: New Microbiol Source Type: research
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