{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Link JS"],"funding":["NIBIB NIH HHS","NIAID NIH HHS","NHLBI NIH HHS","National Institutes of Health","National Science Foundation"],"pagination":["341634"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC10476143"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["1277"],"pubmed_abstract":["Over the last few years, the SARS-CoV-2 pandemic has made the need for rapid, affordable diagnostics more compelling than ever. While traditional laboratory diagnostics like PCR and well-plate ELISA are sensitive and specific, they can be costly and take hours to complete. Diagnostic tests that can be used at the point-of-care or at home, like lateral flow assays (LFAs) are a simple, rapid alternative, but many commercially available LFAs have been criticized for their lack of sensitivity compared to laboratory methods like well-plate ELISAs. The Capillary-Driven Immunoassay (CaDI) device described in this work uses microfluidic channels and capillary action to passively automate the steps of a traditional well-plate ELISA for visual read out. This work builds on prior capillary-flow devices by further simplifying operation and use of colorimetric detection. Upon adding sample, an enzyme-conjugated secondary antibody, wash steps, and substrate are sequentially delivered to test and control lines on a nitrocellulose strip generating a colorimetric response. The end user can visually detect SARS-CoV-2 antigen in 15-20 min by naked eye, or results can be quantified using a smartphone and software such as ImageJ. An analytical detection limit of 83 PFU/mL for SARS-CoV-2 was determined for virus in buffer, and 222 PFU/mL for virus spiked into nasal swabs using image analysis, similar to the LODs determined by traditional well-plate ELISA. Additionally, a visual detection limit of 100 PFU/mL was determined in contrived nasal swab samples by polling 20 untrained end-users. While the CaDI device was used for detecting clinically relevant levels of SARS-CoV-2 in this study, the CaDI device can be easily adapted to other immunoassay applications by changing the reagents and antibodies."],"journal":["Analytica chimica acta"],"pubmed_title":["Capillary flow-driven immunoassay platform for COVID-19 antigen diagnostics."],"pmcid":["PMC10476143"],"funding_grant_id":["U01 HL152405","R01AI132668","UO1-HL152405","R01 AI132668","R01EB031510","NSF STTR 2032222","R01 EB031510"],"pubmed_authors":["Anderson LBR","Geiss BJ","O'Donnell-Sloan JJ","Henry CS","Barstis EJO","Call ZD","Jang I","Link JS","Panraksa Y","Dandy DS","Carrell CS","Bellows RA","Terry JS"],"additional_accession":[]},"is_claimable":false,"name":"Capillary flow-driven immunoassay platform for COVID-19 antigen diagnostics.","description":"Over the last few years, the SARS-CoV-2 pandemic has made the need for rapid, affordable diagnostics more compelling than ever. While traditional laboratory diagnostics like PCR and well-plate ELISA are sensitive and specific, they can be costly and take hours to complete. Diagnostic tests that can be used at the point-of-care or at home, like lateral flow assays (LFAs) are a simple, rapid alternative, but many commercially available LFAs have been criticized for their lack of sensitivity compared to laboratory methods like well-plate ELISAs. The Capillary-Driven Immunoassay (CaDI) device described in this work uses microfluidic channels and capillary action to passively automate the steps of a traditional well-plate ELISA for visual read out. This work builds on prior capillary-flow devices by further simplifying operation and use of colorimetric detection. Upon adding sample, an enzyme-conjugated secondary antibody, wash steps, and substrate are sequentially delivered to test and control lines on a nitrocellulose strip generating a colorimetric response. The end user can visually detect SARS-CoV-2 antigen in 15-20 min by naked eye, or results can be quantified using a smartphone and software such as ImageJ. An analytical detection limit of 83 PFU/mL for SARS-CoV-2 was determined for virus in buffer, and 222 PFU/mL for virus spiked into nasal swabs using image analysis, similar to the LODs determined by traditional well-plate ELISA. Additionally, a visual detection limit of 100 PFU/mL was determined in contrived nasal swab samples by polling 20 untrained end-users. While the CaDI device was used for detecting clinically relevant levels of SARS-CoV-2 in this study, the CaDI device can be easily adapted to other immunoassay applications by changing the reagents and antibodies.","dates":{"release":"2023-01-01T00:00:00Z","publication":"2023 Oct","modification":"2025-04-03T23:48:46.026Z","creation":"2025-04-03T23:48:46.026Z"},"accession":"S-EPMC10476143","cross_references":{"pubmed":["37604607"],"doi":["10.1016/j.aca.2023.341634"]}}