As our device is meant to be used as a diagnosis tool, we considered what safety precautions would have to be taken given that we reach a stage where our device can be tested under real life conditions.

Our first consideration was the bacteria that our device would be built inside. We elected to use E. coli, as it is a risk group 1 organism. Leptospira,the bacteria, we are detecting is a risk group 3 organism, and is banned from use in iGEM. As such we made compromises so that we did not need to use the spirochete.

Our device tests for the presence of RNA from the spirochete Leptospira in the blood. Leptospirosis is a contagious disease, and as such we wanted to find alternatives to having to test blood containing the bacteria directly in order to characterise our device. We decided that instead of designing our device to test directly for Leptospira RNA we would initially design it to test for an analogue RNA thatdoes not code for any specific protein. This avoids having to specifically grow up Leptospira bacteria in our lab, or having to transform another bacteria with a plasmid encoding for Leptospira specific RNA. In this way we eliminate the risk of handling infectious bacterial proteins, and the potential risk of release of a bacteria that is able to produce Leptospira proteins. Another way to work around this problem would have been to transform another bacteria with Leptospira specific RNA but not to include an RBS that would allow the RNA to be translated. We decided that if we were modifying the RNA in such a way, it would be simpler and less risky to use an entirely synthetic RNA sequence as the trigger for the device instead.

A second concern we had was that if we were to test the concentration of Leptospira in the blood that would trigger the diagnosis device, how would we do it without coming in to contact with either Leptospira bacteria, or human blood? Human blood is dangerous to handle, especially for individuals untrained in the specific safety requirements, as it can contain many possible contaminations that may be transmissible to the one handling it. In training labs in university, when students are taught how to screen blood they are encouraged to use their own, however we were hesitant to do this as individual variations in our blood could potentially alter the mechanics of the device, as well as the further ethical implications of testing a diagnosis device on previously untested human blood. We decided that we would order in pre-screened human blood serum that we personally inoculate with modified bacteria carrying the trigger RNA gene. This avoids having to use both our own unscreened blood, or blood from another source, while also sidestepping the issue of using Leptospira.