HARDWARE Prototype 1.0

Introduction

Synthetic biology depends not only on DNA assembly and molecular techniques but also on robust cultivation systems that make biological processes reproducible, scalable, and accessible. For our project, which focuses on the recovery of rare earth elements (REEs) using microalgae, we needed a photobioreactor that could support growth under controlled conditions and enable downstream recovery experiments.

Commercial photobioreactors are often expensive and designed for industrial production. To bridge this gap, we developed a low-cost, modular acrylic-based annular photobioreactor, inspired by established designs in literature [6], [3], [1]. Our reactor provides stable illumination, aeration, and monitoring at a fraction of the cost of commercial systems (approx. 600-650 $ per unit).

By combining accessible off-the-shelf components (LED tubes, aquarium pumps, fans, and inexpensive sensors) with a simple but effective annular design, our device enables reliable algal cultivation. Beyond our project, this hardware contributes to iGEM’s vision of making synthetic biology more affordable, reproducible, and globally accessible.

Design Principles

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Construction and Components

This creates an illuminated annular cultivation chamber of ~18 L.

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Operation and Control

Our reactor is operated under continuous illumination (24 h). The emitted heat from the light module serves as the only heat source for the reactor system. To ensure stable temperatures for algal cultivation, a temperature probe and a regulated fan are used. Aeration is provided by a standard aquarium air pump. CO₂ is fed into the gas line via standard CO₂ tanks used for beer dispensing and brewing. The resulting mixture is infused via perforated base tubing. CO₂ serves as the only carbon source. This autotrophic setting helps inhibit microbial contamination.

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Application in Our Project

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Accessibility and Reproducibility

• Off-the-shelf parts: aquarium hardware, acrylic tubes, LED tubes.
• Affordable: total cost ~$632.
• Easy construction: silicone adhesives + basic tools.
• Open-source: CAD files, schematics, and photos in our wiki and guide.

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Outlook and Future Improvements

• Automation with Raspberry Pi (light, aeration, pH).
• Scaling via scalable reactors.
• Plug-and-play OD sensors.
• Two-stage strategies (e.g., phosphorus starvation).

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Impressions from the Assembly

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R3 Parts (Interactive 3D Previews)

Downloads

For further information on assembly read the following guide.

Guide

The following 3D files’ extensions had to be masked with a .json extension to allow the upload on the wikipage. For usage, download the file and change the extension to .stl .