{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T22:10:30Z","timestamp":1772575830783,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,8,14]],"date-time":"2021-08-14T00:00:00Z","timestamp":1628899200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Toxoplasmosis is the most reported parasitic zoonosis in Europe, with implications in human health and in the veterinary field. There is an increasing need to develop serotyping of Toxoplasma gondii (T. gondii) in view of greater sensitivity and efficiency, through the definition of new targets and new methodologies. Nanotechnology is a promising approach, with impact in the development of point-of-care devices. The aim of this work was to develop a simple but highly efficient method for Toxoplasma gondii serotyping based on gold nanoparticles. A simple colorimetric method was developed using gold nanoparticles modified with the synthetic polymorphic peptide derived from GRA6 antigen specific for type II T. gondii. The method of preparation of the gold nanoprobes and the experimental conditions for the detection were found to be critical for a sensitive discrimination between positive and negative sera. The optimized method was used to detect antibodies anti-GRA6II both in mice and human serum samples. These results clearly demonstrate that a biosensor-based immunoassay using AuNPs conjugated with polymorphic synthetic peptides can be developed and used as a serotyping device<\/jats:p>","DOI":"10.3390\/nano11082065","type":"journal-article","created":{"date-parts":[[2021,8,15]],"date-time":"2021-08-15T22:51:27Z","timestamp":1629067887000},"page":"2065","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Biosensor Based Immunoassay: A New Approach for Serotyping of Toxoplasma gondii"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3891-3924","authenticated-orcid":false,"given":"Susana","family":"Sousa","sequence":"first","affiliation":[{"name":"LAQV, REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169 Porto, Portugal"},{"name":"Center for Parasite Biology and Immunology, National Institute of Health Dr. Ricardo Jorge, 4000 Porto, Portugal"}]},{"given":"Ant\u00f3nio","family":"Castro","sequence":"additional","affiliation":[{"name":"Center for Parasite Biology and Immunology, National Institute of Health Dr. Ricardo Jorge, 4000 Porto, Portugal"},{"name":"Center for the Study of Animal Science (CECA)\/Institute for Agricultural and Agro-Alimentary Science and Technology (ICETA), University of Porto, 4051 Porto, Portugal"}]},{"given":"Jos\u00e9 Manuel","family":"Correia da Costa","sequence":"additional","affiliation":[{"name":"Center for Parasite Biology and Immunology, National Institute of Health Dr. Ricardo Jorge, 4000 Porto, Portugal"},{"name":"Center for the Study of Animal Science (CECA)\/Institute for Agricultural and Agro-Alimentary Science and Technology (ICETA), University of Porto, 4051 Porto, Portugal"}]},{"given":"Eul\u00e1lia","family":"Pereira","sequence":"additional","affiliation":[{"name":"LAQV, REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,14]]},"reference":[{"key":"ref_1","unstructured":"EFSA, European Food Safety Authority (2007). 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