{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T18:44:36Z","timestamp":1785437076612,"version":"3.56.0"},"reference-count":18,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T00:00:00Z","timestamp":1783641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Nanion Technologies"},{"DOI":"10.13039\/501100019166","name":"Center for NanoScience","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100019166","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Ludwig-Maximilians-Universit\u00e4t"},{"name":"Cusanuswerk"},{"id":[{"id":"https:\/\/ror.org\/012b3v785","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"crossref","award":["TI 329\/14-1"],"award-info":[{"award-number":["TI 329\/14-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"crossref","award":["KA 5449\/2-1"],"award-info":[{"award-number":["KA 5449\/2-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"crossref"}]},{"award":["TI 329\/14-1"],"award-info":[{"award-number":["TI 329\/14-1"]}],"id":[{"id":"https:\/\/ror.org\/018mejw64","id-type":"ROR","asserted-by":"publisher"}]},{"award":["KA 5449\/2-1"],"award-info":[{"award-number":["KA 5449\/2-1"]}],"id":[{"id":"https:\/\/ror.org\/018mejw64","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Germany\u2019s Excellence Strategy","award":["EXC 2089\/1\u2014390776260"],"award-info":[{"award-number":["EXC 2089\/1\u2014390776260"]}]},{"DOI":"10.13039\/501100004442","name":"National Science Center","doi-asserted-by":"publisher","award":["Sonata 2019\/35\/D\/ST5\/00958"],"award-info":[{"award-number":["Sonata 2019\/35\/D\/ST5\/00958"]}],"id":[{"id":"10.13039\/501100004442","id-type":"DOI","asserted-by":"publisher"}]},{"award":["Sonata 2019\/35\/D\/ST5\/00958"],"award-info":[{"award-number":["Sonata 2019\/35\/D\/ST5\/00958"]}],"id":[{"id":"https:\/\/ror.org\/03ha2q922","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Transparent conductive interfaces can enable optical pre-assessment of cardiac cell layers while remaining compatible with label-free electrophysiological recording. Here, we evaluated the integration of a monolayer graphene electrode into a capacitive recording platform for the analysis of human-induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) monolayers. hiPSC-CMs cultured on graphene sensors formed confluent, synchronously beating monolayers that could be assessed by light microscopy prior to recording. Capacitive current transients could be recorded from spontaneously beating hiPSC-CM monolayers, supporting the compatibility of transparent graphene interfaces with capacitive recordings from electrically active cardiac cell layers. Signal amplitude and waveform morphology varied across sensors, indicating that recording performance depended strongly on the cell\u2013sensor interface, including cell attachment, monolayer integrity, and capacitive coupling at the sensing surface. A descriptive perturbation sequence using the hERG blocker dofetilide revealed changes in waveform morphology and beat timing across sequential recordings. However, the data do not allow firm attribution to a compound-specific effect and are not intended for quantitative pharmacological characterization. Overall, the results support graphene as a transparent conductive cell\u2013sensor interface, which should be interpreted in the context of cell\u2013substrate interactions at the sensing surface. Combining optical pre-assessment with functional capacitive readout may support integrated workflows. Further studies will be needed to differentiate material-, interface-, and recording-related contributions and to establish reliable conditions for reproducible and scalable recordings.<\/jats:p>","DOI":"10.3390\/s26144383","type":"journal-article","created":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T11:43:34Z","timestamp":1783683814000},"page":"4383","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Transparent Graphene Interfaces for Capacitive Recordings from hiPSC-Derived Cardiomyocyte Monolayers: A Proof-of-Concept Study"],"prefix":"10.3390","volume":"26","author":[{"given":"Melanie","family":"Meincke","sequence":"first","affiliation":[{"name":"Nanion Technologies, Ganghoferstra\u00dfe 70A, 80339 Munich, Germany"},{"name":"Department of Chemistry, Ludwig-Maximilians-Universit\u00e4t, Butenandtstra\u00dfe 5-13, 81377 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2419-3519","authenticated-orcid":false,"given":"Andre","family":"Bazzone","sequence":"additional","affiliation":[{"name":"Nanion Technologies, Ganghoferstra\u00dfe 70A, 80339 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sonja","family":"Stoelzle-Feix","sequence":"additional","affiliation":[{"name":"Nanion Technologies, Ganghoferstra\u00dfe 70A, 80339 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephan","family":"Holzhauser","sequence":"additional","affiliation":[{"name":"Nanion Technologies, Ganghoferstra\u00dfe 70A, 80339 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Barthmes","sequence":"additional","affiliation":[{"name":"Nanion Technologies, Ganghoferstra\u00dfe 70A, 80339 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0819-9248","authenticated-orcid":false,"given":"Lars","family":"Richter","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Ludwig-Maximilians-Universit\u00e4t, Butenandtstra\u00dfe 5-13, 81377 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Izabela","family":"Kami\u0144ska","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Ludwig-Maximilians-Universit\u00e4t, Butenandtstra\u00dfe 5-13, 81377 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"George","sequence":"additional","affiliation":[{"name":"Nanion Technologies, Ganghoferstra\u00dfe 70A, 80339 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philip","family":"Tinnefeld","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Ludwig-Maximilians-Universit\u00e4t, Butenandtstra\u00dfe 5-13, 81377 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9731-2283","authenticated-orcid":false,"given":"Niels","family":"Fertig","sequence":"additional","affiliation":[{"name":"Nanion Technologies, Ganghoferstra\u00dfe 70A, 80339 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,10]]},"reference":[{"key":"ref_1","unstructured":"ICH Harmonised Tripartite Guideline (2005). 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