Bacterial biosensors (which usually contain plasmids with a reporter gene fused to a regulatory promoter) have been shown to be an alternative to traditional analytics for heavy-metal pollutant detection.
Several papers are claiming that they are "better" then traditional analytical techniques, such as inductively coupled plasma spectroscopy, EDAX analysis, and graphene based chem-sensor. However, after reviewing some literature, bacterial biosensors do not seem that much easier/more effective then these other techniques. Sometimes, there sensitivity is bad at lower concentration, and sample processing is still needed for some applications.
Does anybody know the pros and cons of using biosensors over these techniques? How do they compare in respect to cost, durability, accuracy, applicability of the field?
Thanks.
A comprehensive answer on your question would be quite complex. To put it bluntly, I would not perform this kind of research. Please consider that these biosensors detect only a "bioavailable", not strongly complexed fraction of heavy metals. Unfortunately, most legal limits ask for something else, such as the total content of an element or a species. In addition, most of these biosensors are not sensitive enough to detect relevant environmental concentrations or have never been validated with real samples. In addition, in Germany these recombinant bacteria could not be used outside a safety lab due to a very strict GMO legislation.
Adam,
It is complicated to state that bacterial biosensor is worse or better than more traditional techniques. In addition, it is important to check the legislation regarding the use of GMOs (since in this case the bacterium contains a plasmid with exogenous genes) for in situ application.
Regarding the sensitivity of the biosensor, I believe in this case it can be improved depending on the promoter that will be used, or the enzyme itself (if applicable) that will catalyze the reaction.
Regarding the durability of the biosensor, it is important to check the storage mode and temperature. In general, cells are stored at -80°C. I recommend making a stability curve, delimiting a cutoff value for detection sensitivity.
It is possible to develop, however due to the complexity of a cell/microorganism, if possible to use a single enzyme or two-step reaction could be easier, and probably the final cost should be lower.
I hope I have been helpful.
- Badges
- Science topic