This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Growing microorganisms for laboratory experiments or industrial biotechnological process is an activity which involves the use of bioreactors. Although there are many commercially available equipment, most of them lack the flexibility of an open-source solution. This work proposes a cost effective Arduino based bioreactor controller for growing suspended microbial cells. To exemplify its functionality, this study provides the parts list and schematics necessary to make a functional laboratory scale bench top stirred tank bioreactor. Using the built prototype, an E. coli culture is grown maintaining the preset parameters, protein expression is induced and culture is harvested at preset culture density. Automatically recorded process data shows stable environmental parameters and reliable bacterial growing curve.