{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T03:10:02Z","timestamp":1790478602523,"version":"4.1.0"},"reference-count":33,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T00:00:00Z","timestamp":1775779200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Faculty of Associated Medical Sciences Faculty\u2019s research grant","award":["-"],"award-info":[{"award-number":["-"]}]},{"name":"CMU Proactive Researcher, Chiang Mai University","award":["-"],"award-info":[{"award-number":["-"]}]},{"award":["-"],"award-info":[{"award-number":["-"]}],"id":[{"id":"https:\/\/ror.org\/05m2fqn25","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Streptococcus suis is a serious zoonotic pathogen responsible for rapid progression and deadly infections in both humans and pigs. With an increasing number of reported cases and considering the limitations of standard routine identification, a simple, rapid, and cost-effective approach is needed. In this study, a label-free colorimetric assay based on gold nanoparticles (AuNPs) was applied with a specific aptamer, R8-su12. This assay offered simplified detection through observable color change, enabling visual analysis by the naked eye or assessment via UV\u2013Vis spectrophotometry. Under the optimal assay conditions, the detection procedure was carried out within 45 min. The reaction of the aptasensor and other bacterial species, including Staphylococcus aureus, S. pneumoniae, S. pyogenes, Pseudomonas aeruginosa, Escherichia coli, Enterococcus faecium, and E. faecalis, was not present, indicating the specificity of this assay. Moreover, the aptasensor exhibited high sensitivity with a limit of detection (LOD) at 1 CFU of S. suis and had broad reactivity with S. suis serotypes 1, 1\/2, 9, and 14, as well as with S. suis isolated from clinical specimens. Thus, this aptasensor demonstrates proof-of-concept feasibility including clinical sample testing before practical implementation. It holds promise as a practical tool for the early screening and outbreak management of S. suis in a variety of settings, such as clinical laboratories, food safety, and the environment.<\/jats:p>","DOI":"10.3390\/bios16040215","type":"journal-article","created":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T10:20:16Z","timestamp":1775816416000},"page":"215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Aptamer-Based Label-Free Colorimetric Assay Using Gold Nanoparticles for Specific Detection of Streptococcus suis"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4987-5505","authenticated-orcid":false,"given":"Sirikwan","family":"Sangboonruang","sequence":"first","affiliation":[{"name":"Office of Research Administration, Chiang Mai University, Chiang Mai 50200, Thailand"},{"name":"Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2078-3201","authenticated-orcid":false,"given":"Natthawat","family":"Semakul","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Apinyapat","family":"Matchawong","sequence":"additional","affiliation":[{"name":"Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anuchit","family":"Sattaphan","sequence":"additional","affiliation":[{"name":"Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kanokwan","family":"Saengsawang","sequence":"additional","affiliation":[{"name":"Department of Medical Technology, Lampang Hospital, Lampang 52000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6593-2499","authenticated-orcid":false,"given":"Chatchawan","family":"Srisawat","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8812-5139","authenticated-orcid":false,"given":"Khajornsak","family":"Tragoolpua","sequence":"additional","affiliation":[{"name":"Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand"},{"name":"Infectious Diseases Research Unit (IDRU), Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1441-9641","authenticated-orcid":false,"given":"Chayada Sitthidet","family":"Tharinjaroen","sequence":"additional","affiliation":[{"name":"Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand"},{"name":"Infectious Diseases Research Unit (IDRU), Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"567","DOI":"10.1292\/jvms.18-0678","article-title":"High rate misidentification of biochemically determined Streptococcus isolates from swine clinical specimens","volume":"81","author":"Meekhanon","year":"2019","journal-title":"J. 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