This stage of our project required a workable prototype; one that can be used in a real-world setting. We enacted various interactions with experienced stakeholders and incorporated their feedback to better our product. Below are the various ways that we exhibited thorough use of our integrated human practices, and how that positively affected our product development.

Minerals Commission of Ghana

Rethinking the Biosensor Containment: The team switched from the drone sprayer design, to utilizing a stake, so that the sensor could reach deep into the ground.

iGEM Safety and Biosecurity Grants Meeting

Utilizing the U.V Kill Switch: The U.V kill switch was included in the prototype, as it is a crucial way to destroy that bacteria after the biosensor does its job. It was used in the form of an led strip.

Deploying a Hydrogel Capsule: By utilizing a robust hydrogel shell, we can keep the environment safe from the potential threats of the bacteria.

Engineers and Planners – Meeting with Experts

Attach and Detach Mechanism for Stake: This was implemented through the use of a ¾ inch ball valve, so as to separate the biosensor container from the rest of the stake. This will save money and materials.

Making a Preliminary Hole for the Stake: For the prototype, a larger PVC pipe (2 inch) was used to serve as the larger hole to make space for the insertion of the smaller-diameter pipe.

Incorporating Flap Design: The cap for the 2-inch ball valve would shield the stake from heavy rains, and creates an airy environment for the bacteria.

Providing Immediate Feedback to Users: An OLED display was coded in Arduino IDE to reveal the likelihood of gold – based on the color that was sensed by the color sensor – from the two RGB LEDs. The two LEDs are used to simulate the color indicators of two particles [As3+, Fe2+, or Au+].

Labelled diagram of the most recent CAD model – with user feedback incorporated

Working proof of concept for stake-biosensor – with stake plunged into soil

Soldered components provide users with accurate feedback on an OLED screen


With the use of electronics, we were able to design our bio-electronic system. There were numerous stages involved to design the prototype.

Below is a video of the prototype with real-world applications simulations