{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T15:35:16Z","timestamp":1790177716345,"version":"4.1.0"},"reference-count":44,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,5,15]],"date-time":"2023-05-15T00:00:00Z","timestamp":1684108800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Since the global outbreak of coronavirus disease 2019 (COVID-19), it has spread rapidly around the world. The nucleocapsid (N) protein is one of the most abundant SARS-CoV-2 proteins. Therefore, a sensitive and effective detection method for SARS-CoV-2 N protein is the focus of research. Here, we developed a surface plasmon resonance (SPR) biosensor based on the dual signal-amplification strategy of Au@Ag@Au nanoparticles (NPs) and graphene oxide (GO). Additionally, a sandwich immunoassay was utilized to sensitively and efficiently detect SARS-CoV-2 N protein. On the one hand, Au@Ag@Au NPs have a high refractive index and the capability to electromagnetically couple with the plasma waves propagating on the surface of gold film, which are harnessed for amplifying the SPR response signal. On the other hand, GO, which has the large specific surface area and the abundant oxygen-containing functional groups, could provide unique light absorption bands that can enhance plasmonic coupling to further amplify the SPR response signal. The proposed biosensor could efficiently detect SARS-CoV-2 N protein for 15 min and the detection limit for SARS-CoV-2 N protein was 0.083 ng\/mL, with a linear range of 0.1 ng\/mL~1000 ng\/mL. This novel method can meet the analytical requirements of artificial saliva simulated samples, and the developed biosensor had a good anti-interference capability.<\/jats:p>","DOI":"10.3390\/bios13050549","type":"journal-article","created":{"date-parts":[[2023,5,16]],"date-time":"2023-05-16T02:27:04Z","timestamp":1684204024000},"page":"549","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["A Novel SPR Immunosensor Based on Dual Signal Amplification Strategy for Detection of SARS-CoV-2 Nucleocapsid Protein"],"prefix":"10.3390","volume":"13","author":[{"given":"Lirui","family":"Fan","sequence":"first","affiliation":[{"name":"State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China"},{"name":"School of Chemical Engineering, Sichuan University of Science and Engineering, Zigong 643000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bin","family":"Du","sequence":"additional","affiliation":[{"name":"State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fubin","family":"Pei","sequence":"additional","affiliation":[{"name":"State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Hu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shasha","family":"Feng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bing","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhaoyang","family":"Tong","sequence":"additional","affiliation":[{"name":"State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenyuan","family":"Tan","sequence":"additional","affiliation":[{"name":"School of Chemical Engineering, Sichuan University of Science and Engineering, Zigong 643000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xihui","family":"Mu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"25846","DOI":"10.1021\/acsomega.1c04024","article-title":"Multiplex Biosensing for Simultaneous Detection of Mutations in SARS-CoV-2","volume":"6","author":"Xi","year":"2021","journal-title":"ACS Omega"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"4664","DOI":"10.1038\/s41467-021-25015-6","article-title":"SARS-CoV-2 N protein promotes NLRP3 inflammasome activation to induce hyperinflammation","volume":"12","author":"Pan","year":"2021","journal-title":"Nat. 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