{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:24:50Z","timestamp":1760235890790,"version":"build-2065373602"},"reference-count":50,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2021,10,2]],"date-time":"2021-10-02T00:00:00Z","timestamp":1633132800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for the coronavirus disease (COVID-19) pandemic, is sweeping the world today. This study investigates the optical detection of SARS-CoV-2, utilizing the antigen-antibody binding interactions utilizing a light source from a smart phone and a portable spectrophotometer. The proof-of-concept is shown by detecting soluble preparations of spike protein subunits from SARS-CoV-2, followed by detection of the actual binding potential of the SARS-CoV-2 proteins with their corresponding antigens. The measured binding interactions for RBD and NCP proteins with their corresponding antibodies under different conditions have been measured and analyzed. Based on these observations, a \u201chump or spike\u201d in light intensity is observed when a specific molecular interaction takes place between two proteins. The optical responses could further be analyzed using the principle component analysis technique to enhance and allows precise detection of the specific target in a multi-protein mixture.<\/jats:p>","DOI":"10.3390\/s21196596","type":"journal-article","created":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T21:37:49Z","timestamp":1633901869000},"page":"6596","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Optical Detection of SARS-CoV-2 Utilizing Antigen-Antibody Binding Interactions"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1243-5207","authenticated-orcid":false,"given":"Mahmoud Al","family":"Ahmad","sequence":"first","affiliation":[{"name":"Electrical Engineering Department, United Arab Emirates University, Al Ain 15551, United Arab Emirates"},{"name":"Zayed Center for Health Sciences, United Arab Emirates University, Al Ain 15551, United Arab Emirates"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1081-3756","authenticated-orcid":false,"given":"Farah","family":"Mustafa","sequence":"additional","affiliation":[{"name":"Zayed Center for Health Sciences, United Arab Emirates University, Al Ain 15551, United Arab Emirates"},{"name":"Department of Biochemistry, College of Medicine & Health Sciences, Al Ain 20000, United Arab Emirates"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Neena","family":"Panicker","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, College of Medicine & Health Sciences, Al Ain 20000, United Arab Emirates"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tahir A.","family":"Rizvi","sequence":"additional","affiliation":[{"name":"Zayed Center for Health Sciences, United Arab Emirates University, Al Ain 15551, United Arab Emirates"},{"name":"Department of Microbiology and Immunology, College of Medicine & Health Sciences, Al Ain 20000, United Arab Emirates"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1038\/s41586-020-2008-3","article-title":"A New Coronavirus Associated with Human Respiratory Disease in China","volume":"579","author":"Wu","year":"2020","journal-title":"Nature"},{"key":"ref_2","unstructured":"Center for Systems Science and Engineering (2020, July 07). 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