{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T00:30:43Z","timestamp":1775781043320,"version":"3.50.1"},"reference-count":20,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,5,17]],"date-time":"2024-05-17T00:00:00Z","timestamp":1715904000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Republic of Cyprus and the European Regional Development Fund (ERDF) via the Research and Innovation Foundation","award":["ENTERPRISES\/0618\/157"],"award-info":[{"award-number":["ENTERPRISES\/0618\/157"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Cyanobacteria bloom is the term used to describe an abnormal and rapid growth of cyanobacteria in aquatic ecosystems such as lakes, rivers, and oceans as a consequence of anthropic factors, ecosystem degradation, or climate change. Cyanobacteria belonging to the genera Microcystis, Anabaena, Planktothrix, and Nostoc produce and release toxins called microcystins (MCs) into the water. MCs can have severe effects on human and animal health following their ingestion and inhalation. The MC structure is composed of a constant region (composed of five amino acid residues) and a variable region (composed of two amino acid residues). When the MC variable region is composed of arginine and leucine, it is named MC-LR. The most-common methods used to detect the presence of MC-LR in water are chromatographic-based methods (HPLC, LC\/MS, GC\/MS) and immunological-based methods (ELISA). In this work, we developed a new competitive F\u00f6rster resonance energy transfer (FRET) assay to detect the presence of traces of MC-LR in water. Monoclonal antibody anti-MC-LR and MC-LR conjugated with bovine serum albumin (BSA) were labeled with the near-infrared fluorophores CF568 and CF647, respectively. Steady-state fluorescence measurements were performed to investigate the energy transfer process between anti-MC-LR 568 and MC-LR BSA 647 upon their interaction. Since the presence of unlabeled MC-LR competes with the labeled one, a lower efficiency of FRET process can be observed in the presence of an increasing amount of unlabeled MC-LR. The limit of detection (LoD) of the FRET assay is found to be 0.245 nM (0.245 \u00b5g\/L). This value is lower than the provisional limit established by the World Health Organization (WHO) for quantifying the presence of MC-LR in drinking water.<\/jats:p>","DOI":"10.3390\/s24103204","type":"journal-article","created":{"date-parts":[[2024,5,17]],"date-time":"2024-05-17T12:02:23Z","timestamp":1715947343000},"page":"3204","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["A F\u00f6rster Resonance Energy Transfer (FRET)-Based Immune Assay for the Detection of Microcystin-LR in Drinking Water"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5566-2867","authenticated-orcid":false,"given":"Alessandro","family":"Capo","sequence":"first","affiliation":[{"name":"Istituto di Scienze dell\u2019Alimentazione, CNR, URT-Napoli, 80100 Napoli, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angela","family":"Pennacchio","sequence":"additional","affiliation":[{"name":"Istituto di Scienze dell\u2019Alimentazione, CNR, 83100 Avellino, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Concetta","family":"Montagnese","sequence":"additional","affiliation":[{"name":"Istituto di Scienze dell\u2019Alimentazione, CNR, 83100 Avellino, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonis","family":"Hadjiantonis","sequence":"additional","affiliation":[{"name":"CY.R.I.C Cyprus Research and Innovation Center Ltd., Egomi, 2414 Nicosia, Cyprus"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5088-9029","authenticated-orcid":false,"given":"Panayiota","family":"Demosthenous","sequence":"additional","affiliation":[{"name":"CY.R.I.C Cyprus Research and Innovation Center Ltd., Egomi, 2414 Nicosia, Cyprus"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6803-3795","authenticated-orcid":false,"given":"Alessandro","family":"Giusti","sequence":"additional","affiliation":[{"name":"CY.R.I.C Cyprus Research and Innovation Center Ltd., Egomi, 2414 Nicosia, Cyprus"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria","family":"Staiano","sequence":"additional","affiliation":[{"name":"Istituto di Scienze dell\u2019Alimentazione, CNR, 83100 Avellino, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sabato","family":"D\u2019Auria","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Bio-Agroalimentari, CNR, 00185 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Varriale","sequence":"additional","affiliation":[{"name":"Istituto di Scienze dell\u2019Alimentazione, CNR, URT-Napoli, 80100 Napoli, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1016\/j.envint.2013.06.013","article-title":"State of knowledge and concerns on cyanobacterial blooms and cyanotoxins","volume":"59","author":"Merel","year":"2013","journal-title":"Environ. 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