{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T20:03:13Z","timestamp":1789588993414,"version":"build-2803163510"},"reference-count":55,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,5]],"date-time":"2023-01-05T00:00:00Z","timestamp":1672876800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Department of Science &amp; Technology (DST)-Inspire, New Delhi","award":["DST\/INSPIRE Fellowship\/2019\/IF190181"],"award-info":[{"award-number":["DST\/INSPIRE Fellowship\/2019\/IF190181"]}]},{"name":"Department of Science &amp; Technology (DST)-Inspire, New Delhi","award":["IFPDP-68-22"],"award-info":[{"award-number":["IFPDP-68-22"]}]},{"name":"Ministry of Education and the Deanship of Scientific Research (DSR), King Abdulaziz University (KAU), Jeddah, Saudi Arabia","award":["DST\/INSPIRE Fellowship\/2019\/IF190181"],"award-info":[{"award-number":["DST\/INSPIRE Fellowship\/2019\/IF190181"]}]},{"name":"Ministry of Education and the Deanship of Scientific Research (DSR), King Abdulaziz University (KAU), Jeddah, Saudi Arabia","award":["IFPDP-68-22"],"award-info":[{"award-number":["IFPDP-68-22"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Favipiravir (FAV) has become a promising antiviral agent for the treatment of COVID-19. Herein, a green, fast, high-sample-throughput, non-instrumental, and affordable analytical method is proposed based on surfactant-assisted dispersive liquid\u2013liquid microextraction (SA-DLLME) combined with thin-layer chromatography\u2013digital image colourimetry (TLC-DIC) for determining favipiravir in biological and pharmaceutical samples. Triton X-100 and dichloromethane (DCM) were used as the disperser and extraction solvents, respectively. The extract obtained after DLLME procedure was spotted on a TLC plate and allowed to develop with a mobile phase of chloroform:methanol (8:2, v\/v). The developed plate was photographed using a smartphone under UV irradiation at 254 nm. The quantification of FAV was performed by analysing the digital images\u2019 spots with open-source ImageJ software. Multivariate optimisation using Plackett\u2013Burman design (PBD) and central composite design (CCD) was performed for the screening and optimisation of significant factors. Under the optimised conditions, the method was found to be linear, ranging from 5 to 100 \u00b5g\/spot, with a correlation coefficient (R2) ranging from 0.991 to 0.994. The limit of detection (LOD) and limit of quantification (LOQ) were in the ranges of 1.2\u20131.5 \u00b5g\/spot and 3.96\u20134.29 \u00b5g\/spot, respectively. The developed approach was successfully applied for the determination of FAV in biological (i.e., human urine and plasma) and pharmaceutical samples. The results obtained using the proposed methodology were compared to those obtained using HPLC-UV analysis and found to be in close agreement with one another. Additionally, the green character of the developed method with previously reported protocols was evaluated using the ComplexGAPI, AGREE, and Eco-Scale greenness assessment tools. The proposed method is green in nature and does not require any sophisticated high-end analytical instruments, and it can therefore be routinely applied for the analysis of FAV in various resource-limited laboratories during the COVID-19 pandemic.<\/jats:p>","DOI":"10.3390\/molecules28020529","type":"journal-article","created":{"date-parts":[[2023,1,5]],"date-time":"2023-01-05T05:29:48Z","timestamp":1672896588000},"page":"529","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["A Non-Instrumental Green Analytical Method Based on Surfactant-Assisted Dispersive Liquid\u2013Liquid Microextraction\u2013Thin-Layer Chromatography\u2013Smartphone-Based Digital Image Colorimetry(SA-DLLME-TLC-SDIC) for Determining Favipiravir in Biological Samples"],"prefix":"10.3390","volume":"28","author":[{"given":"Bharti","family":"Jain","sequence":"first","affiliation":[{"name":"Central Forensic Science Laboratory, Dakshin Marg, Sector\u201436A, Chandigarh 160036, India"},{"name":"Institute of Forensic Science & Criminology, Panjab University, Chandigarh 160014, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8146-0946","authenticated-orcid":false,"given":"Rajeev","family":"Jain","sequence":"additional","affiliation":[{"name":"Central Forensic Science Laboratory, Dakshin Marg, Sector\u201436A, Chandigarh 160036, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9933-2560","authenticated-orcid":false,"given":"Prashant Kumar","family":"Jaiswal","sequence":"additional","affiliation":[{"name":"School of Earth Sciences, Department of Environmental Sciences, Central University of Rajasthan, NH-8, Bandar Sindri, Ajmer 305817, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2855-5134","authenticated-orcid":false,"given":"Torki","family":"Zughaibi","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia"},{"name":"King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tanvi","family":"Sharma","sequence":"additional","affiliation":[{"name":"Institute of Forensic Science & Criminology, Panjab University, Chandigarh 160014, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3740-8857","authenticated-orcid":false,"given":"Abuzar","family":"Kabir","sequence":"additional","affiliation":[{"name":"International Forensic Research Institute, Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA"},{"name":"Department of Pharmacy, Faculty of Allied Health Science, Daffodil International University, Dhaka 1207, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1336-8210","authenticated-orcid":false,"given":"Ritu","family":"Singh","sequence":"additional","affiliation":[{"name":"School of Earth Sciences, Department of Environmental Sciences, Central University of Rajasthan, NH-8, Bandar Sindri, Ajmer 305817, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1936-2947","authenticated-orcid":false,"given":"Shweta","family":"Sharma","sequence":"additional","affiliation":[{"name":"Institute of Forensic Science & Criminology, Panjab University, Chandigarh 160014, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"106189","DOI":"10.1016\/j.microc.2021.106189","article-title":"Green micellar solvent-free HPLC and spectrofluorimetric determination of favipiravir as one of COVID-19 antiviral regimens","volume":"165","author":"Mikhail","year":"2021","journal-title":"Microchem. 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