Karla R. Castro , Isabela A. Mattioli , Graziela C. Sedenho , Thiago Bertaglia , Antônio F.A. Araújo , Manoel J.A. Lima , Beatriz G.R. da Silva , Mona N. Oliveira , Iris Todeschini , Phelipe M. Vitale , Erika R. Manuli , Geovana M. Pereira , Suzete C. Ferreira , Ester C. Sabino , Emanuel Carrilho , Frank N. Crespilho
{"title":"Plasmonic and quantitative lateral flow assay for grayscale imaging of neutralizing antibodies SARS-CoV-2","authors":"Karla R. Castro , Isabela A. Mattioli , Graziela C. Sedenho , Thiago Bertaglia , Antônio F.A. Araújo , Manoel J.A. Lima , Beatriz G.R. da Silva , Mona N. Oliveira , Iris Todeschini , Phelipe M. Vitale , Erika R. Manuli , Geovana M. Pereira , Suzete C. Ferreira , Ester C. Sabino , Emanuel Carrilho , Frank N. Crespilho","doi":"10.1016/j.talo.2025.100504","DOIUrl":null,"url":null,"abstract":"<div><div>Lateral flow immunoassays (LFIAs) have modernized decentralized mass testing and significantly impacted the healthcare system. It provides a rapid and accessible method for serological testing, which is an important tool for screening patients with past viral phases by detecting antibodies. Here, the development of a quantitative LFIA is presented, in which the receptor-binding domain of Spike protein-specific antibody (anti-S-RBD) in serum samples from previously infected with SARS-CoV-2 patients form an immune complex with the RBD protein immobilized on gold nanoparticles. For quantitative measurements, a methodology was developed based on the plasmonic behavior of gold nanoparticles and using a digital camera that processes images of the test lines in a closed chamber using the CYMK color system. The limits of detection and quantification were 0.22 and 0.70 µg mL<sup>–1</sup>, respectively. The proposed device has a manufacturing cost of less than US$ 1 from synthesizing the bioconjugates, assembly of the LFIA strips, and 3D printing of the cassettes. The platform could detect anti-S-RBD antibodies in human serum samples and can be particularly useful in strategies for monitoring IgG levels in the population.</div></div>","PeriodicalId":436,"journal":{"name":"Talanta Open","volume":"12 ","pages":"Article 100504"},"PeriodicalIF":3.7000,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Talanta Open","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2666831925001067","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Lateral flow immunoassays (LFIAs) have modernized decentralized mass testing and significantly impacted the healthcare system. It provides a rapid and accessible method for serological testing, which is an important tool for screening patients with past viral phases by detecting antibodies. Here, the development of a quantitative LFIA is presented, in which the receptor-binding domain of Spike protein-specific antibody (anti-S-RBD) in serum samples from previously infected with SARS-CoV-2 patients form an immune complex with the RBD protein immobilized on gold nanoparticles. For quantitative measurements, a methodology was developed based on the plasmonic behavior of gold nanoparticles and using a digital camera that processes images of the test lines in a closed chamber using the CYMK color system. The limits of detection and quantification were 0.22 and 0.70 µg mL–1, respectively. The proposed device has a manufacturing cost of less than US$ 1 from synthesizing the bioconjugates, assembly of the LFIA strips, and 3D printing of the cassettes. The platform could detect anti-S-RBD antibodies in human serum samples and can be particularly useful in strategies for monitoring IgG levels in the population.