{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T20:47:27Z","timestamp":1773434847913,"version":"3.50.1"},"reference-count":42,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,1,2]],"date-time":"2022-01-02T00:00:00Z","timestamp":1641081600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FTMC, LAMMC, LEI under inter-institutional agreement No JV-3400-118 founded grant \u2018Development of biodegradable biofuel cells \u2018","award":["No 3400-K34"],"award-info":[{"award-number":["No 3400-K34"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Electrically conductive polymers are promising materials for charge transfer from living cells to the anodes of electrochemical biosensors and biofuel cells. The modification of living cells by polypyrrole (PPy) causes shortened cell lifespan, burdens the replication process, and diminishes renewability in the long term. In this paper, the viability and morphology non-modified, inactivated, and PPy-modified yeasts were evaluated. The results displayed a reduction in cell size, an incremental increase in roughness parameters, and the formation of small structural clusters of polymers on the yeast cells with the increase in the pyrrole concentration used for modification. Yeast modified with the lowest pyrrole concentration showed minimal change; thus, a microbial fuel cell (MFC) was designed using yeast modified by a solution containing 0.05 M pyrrole and compared with the characteristics of an MFC based on non-modified yeast. The maximal generated power of the modified system was 47.12 mW\/m2, which is 8.32 mW\/m2 higher than that of the system based on non-modified yeast. The open-circuit potentials of the non-modified and PPy-modified yeast-based cells were 335 mV and 390 mV, respectively. Even though applying a PPy layer to yeast increases the charge-transfer efficiency towards the electrode, the damage done to the cells due to modification with a higher concentration of PPy diminishes the amount of charge transferred, as the current density drops by 846 \u03bcA\/cm2. This decrease suggests that modification by PPy may have a cytotoxic effect that greatly hinders the metabolic activity of yeast.<\/jats:p>","DOI":"10.3390\/s22010327","type":"journal-article","created":{"date-parts":[[2022,1,9]],"date-time":"2022-01-09T23:08:26Z","timestamp":1641769706000},"page":"327","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Evaluation of a Yeast\u2013Polypyrrole Biocomposite Used in Microbial Fuel Cells"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0865-5880","authenticated-orcid":false,"given":"Antanas","family":"Zinovicius","sequence":"first","affiliation":[{"name":"Department of Mechatronics, Robotics and Digital Manufacturing, Vilnius Gediminas Technical University, 03224 Vilnius, Lithuania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4741-7888","authenticated-orcid":false,"given":"Juste","family":"Rozene","sequence":"additional","affiliation":[{"name":"Department of Mechatronics, Robotics and Digital Manufacturing, Vilnius Gediminas Technical University, 03224 Vilnius, Lithuania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6974-9851","authenticated-orcid":false,"given":"Timas","family":"Merkelis","sequence":"additional","affiliation":[{"name":"Department of Mechatronics, Robotics and Digital Manufacturing, Vilnius Gediminas Technical University, 03224 Vilnius, Lithuania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9758-3913","authenticated-orcid":false,"given":"Ingrida","family":"Bruzaite","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Bioengineering, Faculty of Fundamental Sciences, Vilnius Gediminas Technical University, 10223 Vilnius, Lithuania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0885-3556","authenticated-orcid":false,"given":"Arunas","family":"Ramanavicius","sequence":"additional","affiliation":[{"name":"Department of Physical Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, 03225 Vilnius, Lithuania"},{"name":"Laboratory of Nanotechnology, State Research Institute Centre for Physical Sciences and Technology, 02300 Vilnius, Lithuania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5936-9900","authenticated-orcid":false,"given":"Inga","family":"Morkvenaite-Vilkonciene","sequence":"additional","affiliation":[{"name":"Department of Mechatronics, Robotics and Digital Manufacturing, Vilnius Gediminas Technical University, 03224 Vilnius, Lithuania"},{"name":"Laboratory of Electrochemical Energy Conversion, State Research Institute Centre for Physical Sciences and Technology, 10257 Vilnius, Lithuania"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Andriukonis, E., Celiesiute-Germaniene, R., Ramanavicius, S., Viter, R., and Ramanavicius, A. 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