# Open Source DIY Hardware

Being in the measurement track and having a team of highly motivated engineering and computer science students, we tackled the challenge to build, document and evaluate our open source hardware approach.

For our daily tasks in the lab, two key devices were detected: fluorometer and OD-meter. As we use GFP most of the time, the fluorometer is designed to work best with GFP. For modularity reasons, and re-usability, it is designed such that a change to another fluorescence protein is easy.

Besides the mandatory $\mu$-controller architecture, we worked together with the Fablab Aachen to construct the device. There we have the chance to use laser cutters and 3D printers.

The core component for detecting the light intensity is the cuvette holder. Please find the 3D model we printed below:

This cuvette holder can be used for both devices: the whole in the bottom is used for fluorescence measurement, the two opposite wholes are used for the light sensor and the LED for optical density measurement respectively.

The key ingredients for our combined optical density/fluorescence (OD/F) device then are:

• Arduino UNO R3 (or equivalent)