Sorting the main bottlenecks to use paper-based microbial fuel cells as convenient and practical analytical devices for environmental toxicity testing

GONZALEZ PABON MARIA JESUS; EDUARDO CORTON; FIGUEREDO FEDERICO

CHEMOSPHERE

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2021 vol. 265 p. 1 - 11

0045-6535

Three of the main bottlenecks not before addressed for practical, point of need use of microbial fuel cell (MFC) analytical devices were surpassed in this work: i) The use a diffusive barrier, hence the electrogenic biofilm, for toxicity testing in water, ii) The longer enrichment/stabilization time made in laboratory environment to produce a biofilm over the electrode, and iii) The difficulty to compare results obtained from MFCs based on electrogenic biofilms with standardized bioassays, a setback to be adopted as a new method. Here we show an easy way to determine water toxicity by employing a bacterium in suspension, as biorecognition agent in a paper-based MFC containing an electron carrier (or mediator) to facilitate charge transfer from the bacteria to the anode. In this way, there is no need to use biofilms, avoiding their inconvenient when MFC are used. As far as we know this is the first paper-based MFC containing P. putida KT2440, a well characterized non-pathogenic bacteria previously used in standardized water toxicity bioassays. The results were obtained in 80 min and the effective concentration 50 of 9.02 mg L-1 calculated for Zn2+ (a reference toxic agent) was successfully compared with already published and ISO standardized bioassays showing promising future for this technology. The practical design and cost of the paper-based MFC toxicity test presented here, less than $ 1 U.S. dollars, open a new market possibility for rapid and easy to use MFCs analytical devices.