The trigger for the cell death is heavily dependant on the project application and the cell encapsulation mechanism. Possible ideas proposed include:
- Hypoxic conditions caused by complete encapsulation in a compound through which oxygen cannot diffuse (not for the alginate capsule, only the CaCO3/ salt capsule)
- Timer mechanism continuing from drug production timer/threshold
- External factor added manually to trigger genetic removal response.
- Environmental Sensor mechanism, different environment once capsule has been formed. depends on capsule again
- RNA thermometer (biobrick characterised by TU Delft '08)