There is something dangerous in the water,

and you can’t even see it...

Paralytic shellfish toxins (PST), such as saxitoxin and tetrodotoxin, are neurotoxins that cause paralytic shellfish poisoning (PSP) by blocking the sodium channels in nerve cell membranes. Symptoms of PSP range from lightheadedness, headache, and diarrhea, all the way to flaccid paralysis, respiratory failure, and even death.

Source of toxins

Source of toxins

These toxins can be found in both marine and freshwater environments as they are naturally produced by certain species of marine dinoflagellates and freshwater cyanobacteria. Wild bivalve shellfish that grow during harmful algal blooms accumulate these toxins.

Due to climate change, there is now an increase in harmful algae blooms around the world, and worryingly also in regions where there were no algae blooms before. With increasing seafood demand, there is an increased risk of paralytic shellfish poisoning after consuming contaminated bivalves, crabs, or even fish. (insert data of increased harmful algal blooms & increased seafood demand)

Current Practice

Currently, lab tests like mouse-poison bioassay and high-performance liquid chromatography (HPLC) are used to detect PST and mitigate the risks, but they both have downsides that can not be ignored. We think we can do better……


We found a way that is



specific, and


Our team - ShellBi -

is designing a prokaryotic biosensor that can detect paralytic shellfish toxins (PST) by utilizing the antagonism between saxitoxin (STX) and veratridine (VTD) in conjunction \with the two-component system of E. coli.
With the addition of fluorescent proteins, it can be easy to tell if a sample contains PST levels exceeding international standards by its red (toxins present) or green light (toxins absent). (insert animation/picture of the FP)