{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T15:14:29Z","timestamp":1774365269967,"version":"3.50.1"},"reference-count":42,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,9,15]],"date-time":"2022-09-15T00:00:00Z","timestamp":1663200000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Industrial Development and Logistics Program (NIDLP)","award":["20-0103"],"award-info":[{"award-number":["20-0103"]}]},{"name":"National Industrial Development and Logistics Program (NIDLP)","award":["20-0051"],"award-info":[{"award-number":["20-0051"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Since the COVID-19 pandemic outbreak in the world, many countries have searched for quick diagnostic tools to detect the virus. There are many ways to design diagnostic assays; however, each may have its limitations. A quick, sensitive, specific, and simple approach is essential for highly rapidly transmitted infections, such as SARS-CoV-2. This study aimed to develop a rapid and cost-effective diagnostic tool using a one-step Reverse Transcriptase Loop-Mediated Isothermal Amplification (RT-LAMP) approach. The results were observed using the naked eye within 30\u201360 min using turbidity or colorimetric analysis. The sensitivity, specificity, and lowest limit of detection (LoD) for SARS-CoV-2 RNA against the RT-LAMP assay were assessed. This assay was also verified and validated against commercial quantitative RT-PCR used by health authorities in Saudi Arabia. Furthermore, a quick and direct sampling from the saliva, or buccal cavity, was applied after simple modification, using proteinase K and heating at 98 \u00b0C for 5 min to avoid routine RNA extraction. This rapid single-tube diagnostic tool detected COVID-19 with an accuracy rate of 95% for both genes (ORF1a and N) and an LoD for the ORF1a and N genes as 39 and 25 copies\/reaction, respectively. It can be potentially used as a high-throughput national screening for different respiratory-based infections within the Middle East region, such as the MERS virus or major zoonotic pathogens such as Mycobacterium paratuberculosis and Brucella spp., particularly in remote and rural areas where lab equipment is limited.<\/jats:p>","DOI":"10.3390\/diagnostics12092232","type":"journal-article","created":{"date-parts":[[2022,9,15]],"date-time":"2022-09-15T22:11:10Z","timestamp":1663279870000},"page":"2232","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Development and Validation of Reverse Transcriptase Loop-Mediated Isothermal Amplification (RT-LAMP) as a Simple and Rapid Diagnostic Tool for SARS-CoV-2 Detection"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0715-6780","authenticated-orcid":false,"given":"Ahmad M.","family":"Aldossary","sequence":"first","affiliation":[{"name":"National Center of Biotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0716-3251","authenticated-orcid":false,"given":"Essam A.","family":"Tawfik","sequence":"additional","affiliation":[{"name":"National Center of Biotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Musaad A.","family":"Altammami","sequence":"additional","affiliation":[{"name":"National Center of Biotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Azzam A.","family":"Alquait","sequence":"additional","affiliation":[{"name":"National Center of Biotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6006-395X","authenticated-orcid":false,"given":"Rayan Y.","family":"Booq","sequence":"additional","affiliation":[{"name":"National Center of Biotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2970-1882","authenticated-orcid":false,"given":"Bandar K.","family":"Sendy","sequence":"additional","affiliation":[{"name":"National Center of Biotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohammed S.","family":"Alarawi","sequence":"additional","affiliation":[{"name":"Computational Bioscience Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Takashi","family":"Gojobori","sequence":"additional","affiliation":[{"name":"Computational Bioscience Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0381-757X","authenticated-orcid":false,"given":"Asmaa M.","family":"Altamimi","sequence":"additional","affiliation":[{"name":"Public Health Laboratory, Public Health Authority, Riyadh 13354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Taghreed A.","family":"Alaifan","sequence":"additional","affiliation":[{"name":"Public Health Laboratory, Public Health Authority, Riyadh 13354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ahmed M.","family":"Albarrag","sequence":"additional","affiliation":[{"name":"Public Health Laboratory, Public Health Authority, Riyadh 13354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Essam J.","family":"Alyamani","sequence":"additional","affiliation":[{"name":"National Center of Biotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 12354, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"450","DOI":"10.1038\/s41591-020-0820-9","article-title":"The proximal origin of SARS-CoV-2","volume":"26","author":"Andersen","year":"2020","journal-title":"Nat. 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