{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,2]],"date-time":"2026-11-02T21:52:53Z","timestamp":1793656373277,"version":"4.5.1"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,22]],"date-time":"2026-02-22T00:00:00Z","timestamp":1771718400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"US National Institutes of Health","doi-asserted-by":"publisher","award":["R01AI141549"],"award-info":[{"award-number":["R01AI141549"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"US National Institutes of Health","doi-asserted-by":"publisher","award":["R01AI152579"],"award-info":[{"award-number":["R01AI152579"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"US National Institutes of Health","doi-asserted-by":"publisher","award":["T32AI170496"],"award-info":[{"award-number":["T32AI170496"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Silver Innovation Award"},{"name":"Oregon Health & Science University Biophysics Shared Resources Core and equipment","award":["S10OD023413"],"award-info":[{"award-number":["S10OD023413"]}],"id":[{"id":"https:\/\/ror.org\/009avj582","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Lateral flow assays (LFAs) are among the most successful technologies for point-of-care and at-home testing, but further advances are needed to reduce costs and accelerate development. Alpaca-derived nanobodies (Nbs), single-domain antibody fragments, are promising immunoassay reagents across diverse applications. Their small size and ease of recombinant production make them particularly well suited for diagnostics. Here, we present a paper-based LFA targeting the SARS-CoV-2 nucleocapsid (N) protein that exclusively uses Nbs for direct antigen detection. We also demonstrate in-house synthesis of Nb-coated gold nanoparticles, enabling instrument-free visual readout and detection of N protein down to 40 ng\/mL. This design avoids components that require mammalian cell culture and can be produced entirely from in-house reagents, simplifying manufacturing and lowering component costs. Because the assay is read visually without an external reader, it is well suited for deployment in resource-limited settings. Together, these results highlight the speed and practicality of developing Nb-based LFAs and suggest a broadly applicable strategy for detecting other clinically important disease biomarkers.<\/jats:p>","DOI":"10.3390\/bios16020132","type":"journal-article","created":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T08:58:21Z","timestamp":1771837101000},"page":"132","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Nanobody-Based Lateral Flow Assay for Point-of-Care Diagnostics"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2533-7668","authenticated-orcid":false,"given":"Timothy A.","family":"Bates","sequence":"first","affiliation":[{"name":"Department of Molecular Microbiology and Immunology, Oregon Health & Sciences University, Portland, OR 97239, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sintayehu K.","family":"Gurmessa","sequence":"additional","affiliation":[{"name":"Department of Molecular Microbiology and Immunology, Oregon Health & Sciences University, Portland, OR 97239, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jules B.","family":"Reyes-Weinstein","sequence":"additional","affiliation":[{"name":"Department of Molecular Microbiology and Immunology, Oregon Health & Sciences University, Portland, OR 97239, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eric","family":"Barklis","sequence":"additional","affiliation":[{"name":"Department of Molecular Microbiology and Immunology, Oregon Health & Sciences University, Portland, OR 97239, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8575-4164","authenticated-orcid":false,"given":"Fikadu G.","family":"Tafesse","sequence":"additional","affiliation":[{"name":"Department of Molecular Microbiology and Immunology, Oregon Health & Sciences University, Portland, OR 97239, USA"},{"name":"Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1997","DOI":"10.1016\/S0140-6736(21)00673-5","article-title":"The Lancet Commission on Diagnostics: Transforming Access to Diagnostics","volume":"398","author":"Fleming","year":"2021","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e001179","DOI":"10.1136\/bmjgh-2018-001179","article-title":"Importance of Diagnostics in Epidemic and Pandemic Preparedness","volume":"4","author":"Nkengasong","year":"2019","journal-title":"BMJ Glob. 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