{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T23:28:33Z","timestamp":1768346913866,"version":"3.49.0"},"reference-count":42,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T00:00:00Z","timestamp":1768262400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["UID\/50017\/2025"],"award-info":[{"award-number":["UID\/50017\/2025"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["LA\/P\/0094\/2020"],"award-info":[{"award-number":["LA\/P\/0094\/2020"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["UID\/50011\/2025"],"award-info":[{"award-number":["UID\/50011\/2025"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["LA\/P\/0006\/2020"],"award-info":[{"award-number":["LA\/P\/0006\/2020"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["LA\/P\/0037\/2020"],"award-info":[{"award-number":["LA\/P\/0037\/2020"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["UIDB\/50025\/2020"],"award-info":[{"award-number":["UIDB\/50025\/2020"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["UIDP\/50025\/2020"],"award-info":[{"award-number":["UIDP\/50025\/2020"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["2022.01619.PTDC"],"award-info":[{"award-number":["2022.01619.PTDC"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["UIDB\/00481\/2020"],"award-info":[{"award-number":["UIDB\/00481\/2020"]}]},{"name":"National Funds through the Portuguese Science and Technology Foundation","award":["UIDP\/00481\/2020"],"award-info":[{"award-number":["UIDP\/00481\/2020"]}]},{"DOI":"10.13039\/501100000780","name":"European Union under the REFRESH\u2014Research Excellence For Region Sustainability and High-tech Industries project","doi-asserted-by":"publisher","award":["CZ.10.03.01\/00\/22_003\/0000048"],"award-info":[{"award-number":["CZ.10.03.01\/00\/22_003\/0000048"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministry of Education, Youth, and Sports of the Czech Republic","award":["SP2026\/028 and SP2026\/012"],"award-info":[{"award-number":["SP2026\/028 and SP2026\/012"]}]},{"name":"FCT\/MCTES","award":["UI\/BD\/153066\/2022"],"award-info":[{"award-number":["UI\/BD\/153066\/2022"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Aquaculture is a crucial global food production sector that faces challenges in water quality management, food safety, and stress-related health concerns in aquatic species. Cortisol, a key stress biomarker in fish, and Escherichia coli (E. coli) contamination in bivalve mollusks are critical indicators that require sensitive and real-time detection methods. Liquid crystal (LC)-based immunosensors have emerged as a promising solution for detecting biological analytes due to their high sensitivity, rapid response, and label-free optical detection capabilities. Therefore, this study explores the development and application of LC-based immunosensors for the detection of cortisol in artificial and real recirculating aquaculture system (RAS) samples, as well as E. coli in real contaminated water and clam samples during the depuration processes of bivalve mollusks. The biosensors exhibited the capacity to detect cortisol with a response time in seconds and a limit of detection (LOD) of 0.1 ng\/mL. Furthermore, they demonstrated specificity to cortisol when tested against different interfering substances, including testosterone, glucose, and cholesterol. Furthermore, it was possible to correlate cortisol concentrations in different filtration stages and track E. coli contamination during depuration. The results confirm the feasibility of LC-based immunosensors as a user-friendly, portable, and efficient diagnostic tool for aquaculture applications.<\/jats:p>","DOI":"10.3390\/bios16010059","type":"journal-article","created":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T15:52:57Z","timestamp":1768319577000},"page":"59","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Real-Time Monitoring of Microbial Contamination and Stress Biomarkers with Liquid Crystal-Based Immunosensors for Food Safety Assessment"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2752-1629","authenticated-orcid":false,"given":"Maria Simone","family":"Soares","sequence":"first","affiliation":[{"name":"CICECO\u2013Aveiro Institute of Materials & Physics Department, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"},{"name":"I3N & Physics Department, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9839-6290","authenticated-orcid":false,"given":"Andreia C. M.","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"CESAM\u2014Centre for Environmental and Marine Studies and Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1924-3072","authenticated-orcid":false,"given":"S\u00edlvia. F. S.","family":"Pires","sequence":"additional","affiliation":[{"name":"CESAM\u2014Centre for Environmental and Marine Studies and Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0879-9470","authenticated-orcid":false,"given":"Amadeu M. V. M.","family":"Soares","sequence":"additional","affiliation":[{"name":"CESAM\u2014Centre for Environmental and Marine Studies and Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0190-2298","authenticated-orcid":false,"given":"Ana P. L.","family":"Costa","sequence":"additional","affiliation":[{"name":"SEAentia-Parque Tecnol\u00f3gico de Cantanhede, N\u00facleo 04 Lote 2, 3060-197 Cantanhede, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7459-2043","authenticated-orcid":false,"given":"Jan","family":"Nedoma","sequence":"additional","affiliation":[{"name":"Department of Telecommunications, VSB\u2013Technical University of Ostrava, 70800 Ostrava, Czech Republic"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7356-8455","authenticated-orcid":false,"given":"Pedro L.","family":"Almeida","sequence":"additional","affiliation":[{"name":"I3N\u2013CENIMAT, School of Sciences and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"},{"name":"UnIRE, ISEL, Polytechnic University of Lisbon, 1959-007 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9685-7479","authenticated-orcid":false,"given":"Nuno","family":"Santos","sequence":"additional","affiliation":[{"name":"I3N & Physics Department, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8596-5092","authenticated-orcid":false,"given":"Carlos","family":"Marques","sequence":"additional","affiliation":[{"name":"CICECO\u2013Aveiro Institute of Materials & Physics Department, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"},{"name":"Department of Physics, VSB\u2013Technical University of Ostrava, 70800 Ostrava, Czech Republic"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Martos-Sitcha, J.A., Mancera, J.M., Prunet, P., and Magnoni, L.J. 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