Miniaturized electrochemical biosensor based on whole-cell for heavy metal ions detection in water.
Emanuele L SciutoSalvatore PetraliaJan R van der MeerSebania LibertinoPublished in: Biotechnology and bioengineering (2021)
The heavy metals pollution represents one of the important issues in the environmental field since it is involved in many pathologies from cancer, neurodegenerative, and metabolic diseases. We propose an innovative portable biosensor for the determination of traces of trivalent arsenic (As(III)) and bivalent mercury (Hg(II)) in water. The system implements a strategy combining two advanced sensing modules consisting in (a) a whole cell based on engineered Escherichia coli as selective sensing element towards the metals and (b) an electrochemical miniaturised silicon device with three microelectrodes and a portable reading system. The sensing mechanism relies on the selective recognition from the bacterium of given metals producing the 4-aminophenol redox active mediator detected through a cyclic voltammetry analysis. The miniaturized biosensor is able to operate a portable, robust, and high-sensitivity detection of As(III) with a sensitivity of 0.122 µA ppb-1 , LoD of 1.5 ppb, and a LoQ of 5 ppb. The LoD value is one order of magnitude below of the value indicated to WHO to be dangerous (10 μg/L). The system was proved to be fully versatile being effective in the detection of Hg(II) as well. A first study on Hg(II) showed sensitivity value of 2.11 µA/ppb a LOD value of 0.1 ppb and LoQ value of 0.34 ppb. Also in this case, the detected LOD was 10 times lower than that indicated by WHO (1 ppb). These results pave the way for advanced sensing strategies suitable for the environmental monitoring and the public safety.
Keyphrases
- label free
- heavy metals
- health risk assessment
- health risk
- gold nanoparticles
- human health
- risk assessment
- escherichia coli
- quantum dots
- sensitive detection
- loop mediated isothermal amplification
- single cell
- fluorescent probe
- healthcare
- aqueous solution
- sewage sludge
- cell therapy
- multidrug resistant
- molecularly imprinted
- pseudomonas aeruginosa
- climate change
- cystic fibrosis
- staphylococcus aureus
- bone marrow
- particulate matter
- electron transfer
- life cycle
- squamous cell
- biofilm formation
- papillary thyroid