{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T20:50:03Z","timestamp":1768078203079,"version":"3.49.0"},"reference-count":45,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2023,7,28]],"date-time":"2023-07-28T00:00:00Z","timestamp":1690502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The COST (European Cooperation in Science and Technology) action PERIAMAR","award":["CA18221"],"award-info":[{"award-number":["CA18221"]}]},{"name":"The COST (European Cooperation in Science and Technology) action PERIAMAR","award":["UIDP\/50017\/2020+UIDB\/50017\/2020+ LA\/P\/0094\/2020"],"award-info":[{"award-number":["UIDP\/50017\/2020+UIDB\/50017\/2020+ LA\/P\/0094\/2020"]}]},{"name":"The COST (European Cooperation in Science and Technology) action PERIAMAR","award":["POCI-01-0145-FEDER-030718"],"award-info":[{"award-number":["POCI-01-0145-FEDER-030718"]}]},{"name":"Portuguese Foundation for Science and Technology","award":["CA18221"],"award-info":[{"award-number":["CA18221"]}]},{"name":"Portuguese Foundation for Science and Technology","award":["UIDP\/50017\/2020+UIDB\/50017\/2020+ LA\/P\/0094\/2020"],"award-info":[{"award-number":["UIDP\/50017\/2020+UIDB\/50017\/2020+ LA\/P\/0094\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology","award":["POCI-01-0145-FEDER-030718"],"award-info":[{"award-number":["POCI-01-0145-FEDER-030718"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>Sodium lauryl ether sulphate (SLEnS) is an anionic surfactant that is widely used in many fields, such as cosmetics and detergents, among others. This study evaluated the influence of the number of ethylene oxide (EO) units, present in the head group of SLEnS, on its cytotoxicity to the A6 cell line of Xenopus laevis using MTT and resazurin assays. The A6 cell line was exposed for 48 h to six SLEnS variants: SLE0S, SLE1S, SLE4S, SLE11S, SLE30S, and SLE50S (subscript values correspond to the number of EO units). Overall, the six variants impaired the A6 cells\u2019 viability at low concentrations for the MTT assay, with the median lethal concentrations (LC50,48h) ranging between 0.398 and 0.554 mg\/L and for the resazurin assay between 0.557 and 0.969 mg\/L. Further, the obtained results indicate SLEnS variants with fewer EO units to be the most cytotoxic in the resazurin assay; although a similar cytotoxicity pattern was observed with the MTT assay, a significant association between the number of EO units and the values of LC50 was not found. This result highlights the usefulness of in vitro assays with A6 cell lines as a first screening tool for assessing the structure\u2013toxicity relationship of this type of surfactant, also providing a baseline for the development of environmentally friendlier chemical compounds while still maintaining their efficiency.<\/jats:p>","DOI":"10.3390\/app13158745","type":"journal-article","created":{"date-parts":[[2023,7,31]],"date-time":"2023-07-31T03:30:02Z","timestamp":1690774202000},"page":"8745","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["The Number of Ethylene Oxide Groups of Sulphate-Based Surfactants Influences the Cytotoxicity of Mixed Micelles to an Amphibian Cell Line"],"prefix":"10.3390","volume":"13","author":[{"given":"Sebastian","family":"Topliceanu","sequence":"first","affiliation":[{"name":"Faculty of Natural and Agricultural Sciences, Ovidius University Constan\u0163a, 1 Universit\u0103\u0163ii Street, 900470 Constan\u0163a, Romania"},{"name":"Centre for Research and Development of the Morphological and Genetic Studies of Malignant Pathology, Ovidius University Constan\u0163a, 145 Tomis Blvd., 900591 Constan\u0163a, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5734-4021","authenticated-orcid":false,"given":"Monica","family":"Almeida","sequence":"additional","affiliation":[{"name":"Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Miguel","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2959-014X","authenticated-orcid":false,"given":"Dan","family":"Cog\u0103lniceanu","sequence":"additional","affiliation":[{"name":"Faculty of Natural and Agricultural Sciences, Ovidius University Constan\u0163a, 1 Universit\u0103\u0163ii Street, 900470 Constan\u0163a, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9325-0329","authenticated-orcid":false,"given":"Isabel","family":"Lopes","sequence":"additional","affiliation":[{"name":"Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1366","DOI":"10.1016\/j.scitotenv.2018.06.293","article-title":"Role of surfactant headgroups on the toxicity of SLEnS-LAS mixed micelles: A case study using microtox test","volume":"643","author":"Martins","year":"2018","journal-title":"Sci. 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