{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T09:04:36Z","timestamp":1785834276753,"version":"3.56.0"},"reference-count":54,"publisher":"Wiley","issue":"6","license":[{"start":{"date-parts":[[2018,7,8]],"date-time":"2018-07-08T00:00:00Z","timestamp":1531008000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"funder":[{"DOI":"10.13039\/501100010221","name":"Higher Education Commision, Pakistan","doi-asserted-by":"publisher","award":["Research Project # 20\u20103968"],"award-info":[{"award-number":["Research Project # 20\u20103968"]}],"id":[{"id":"10.13039\/501100010221","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["analyticalsciencejournals.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Luminescence"],"published-print":{"date-parts":[[2018,9]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>A stability\u2010indicating spectrofluorimetric method has been developed for the simultaneous assay of riboflavin (RF) and photoproducts, formylmethylflavin (FMF), lumichrome (LC) and lumiflavin (LF) in aqueous solution. The method is based on the extraction of LC formed in acid solution and LC and LF formed in alkaline solution with chloroform at pH\u00a02.0 and their assay by fluorescence measurements at 478 and 530\u00a0nm, respectively. The aqueous phase, on readjustment of the pH to 6.5, is used to extract FMF with chloroform and its assay is carried out at 530\u00a0nm. The aqueous phase is then used for the assay of RF at 530\u00a0nm. The proposed method gives more accurate results for the assay of RF compared to those of the United States Pharmacopeia (USP) spectrofluorimetric method which does not take into account the presence of RF photoproducts having similar fluorescence characteristics. The proposed method along with the USP method has been applied to the study of the kinetics of photolysis of RF, assay of stored commercial vitamin preparations and their radiated samples. The results show that the USP method does not distinguish between the fluorescence of RF and its photoproducts, and, therefore, gives erroneous results with about 11% excess in the quantity of the vitamin compared to that of the proposed method. This is due to the interference of the fluorescence of photoproducts in the assay of RF. The method has been validated for various analytical parameters according to the guideline of the International Council for Harmonization (ICH).<\/jats:p>","DOI":"10.1002\/bio.3510","type":"journal-article","created":{"date-parts":[[2018,7,8]],"date-time":"2018-07-08T22:19:37Z","timestamp":1531088377000},"page":"1070-1080","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Stability\u2010indicating spectrofluorimetric method for the assay of riboflavin and photoproducts: Kinetic applications"],"prefix":"10.1002","volume":"33","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8817-3595","authenticated-orcid":false,"given":"Iqbal","family":"Ahmad","sequence":"first","affiliation":[{"name":"Baqai Institute of Pharmaceutical Sciences Baqai Medical University  Karachi Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3822-7588","authenticated-orcid":false,"given":"Zubair","family":"Anwar","sequence":"additional","affiliation":[{"name":"Baqai Institute of Pharmaceutical Sciences Baqai Medical University  Karachi Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6333-8178","authenticated-orcid":false,"given":"Muhammad Ali","family":"Sheraz","sequence":"additional","affiliation":[{"name":"Baqai Institute of Pharmaceutical Sciences Baqai Medical University  Karachi Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0731-1237","authenticated-orcid":false,"given":"Sofia","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Baqai Institute of Pharmaceutical Sciences Baqai Medical University  Karachi Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saif\u2010ur\u2010Rehman","family":"Khattak","sequence":"additional","affiliation":[{"name":"Central Drug Laboratories, Ministry of Health, DRAP  Block\u2010B, S.M.C.H. Karachi Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2018,7,8]]},"reference":[{"key":"e_1_2_7_2_1","doi-asserted-by":"publisher","DOI":"10.1042\/bj0470114"},{"key":"e_1_2_7_3_1","doi-asserted-by":"publisher","DOI":"10.1016\/0003-9861(57)90320-X"},{"key":"e_1_2_7_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/0926-6585(65)90221-9"},{"key":"e_1_2_7_5_1","doi-asserted-by":"publisher","DOI":"10.1039\/qr9672100043"},{"key":"e_1_2_7_6_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1751-1097.1977.tb07495.x"},{"key":"e_1_2_7_7_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1751-1097.1977.tb07354.x"},{"key":"e_1_2_7_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/hlca.19790620227"},{"key":"e_1_2_7_9_1","doi-asserted-by":"publisher","DOI":"10.1039\/cs9821100015"},{"key":"e_1_2_7_10_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jphotobiol.2004.11.010"},{"key":"e_1_2_7_11_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jphotobiol.2008.07.005"},{"key":"e_1_2_7_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijpharm.2010.01.042"},{"key":"e_1_2_7_13_1","doi-asserted-by":"publisher","DOI":"10.1208\/s12249-013-0067-6"},{"key":"e_1_2_7_14_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jphotobiol.2016.02.010"},{"key":"e_1_2_7_15_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jphotobiol.2017.05.033"},{"key":"e_1_2_7_16_1","first-page":"222","volume":"10","author":"Sakai K.","year":"1956","journal-title":"Med. Sci. (Japan)"},{"key":"e_1_2_7_17_1","first-page":"428","volume":"12","author":"Rutter W. J.","year":"1958","journal-title":"Acta Chem. Scand."},{"key":"e_1_2_7_18_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja00758a037"},{"key":"e_1_2_7_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/0009-2614(77)85329-3"},{"key":"e_1_2_7_20_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1751-1097.1981.tb09022.x"},{"key":"e_1_2_7_21_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1432-1033.1975.tb02274.x"},{"key":"e_1_2_7_22_1","unstructured":"S.Udenfriend Fluorescence Assay in Biology and Medicine Academic Press New York 1969 297."},{"key":"e_1_2_7_23_1","unstructured":"J.Koziol Methods in Enzymology Academic Press New York 1971 253."},{"key":"e_1_2_7_24_1","first-page":"144","volume":"49","author":"Knobloch E.","year":"1979","journal-title":"Int. J. Vitam. Nutr. Res."},{"key":"e_1_2_7_25_1","first-page":"483","volume":"41","author":"Barary M.","year":"1986","journal-title":"Pharmazie"},{"key":"e_1_2_7_26_1","doi-asserted-by":"publisher","DOI":"10.1081\/AL-120013047"},{"key":"e_1_2_7_27_1","doi-asserted-by":"publisher","DOI":"10.5740\/jaoacint.9-493"},{"key":"e_1_2_7_28_1","volume-title":"Assay of Vitamins in Pharmaceutical Preparations","author":"Hashmi M. H.","year":"1973"},{"key":"e_1_2_7_29_1","volume-title":"Methods of Vitamin Assay","author":"Shah J. J.","year":"1985"},{"key":"e_1_2_7_30_1","doi-asserted-by":"publisher","DOI":"10.1186\/1475-2891-10-47"},{"key":"e_1_2_7_31_1","volume-title":"Vitamin Analysis for the Health and Food Sciences","author":"Eitenmiller R. R.","year":"2008"},{"key":"e_1_2_7_32_1","volume-title":"United States Pharmacopeial Convention, Inc.","author":"United States Pharmacopeia 30\/National Formulary 25","year":"2016"},{"key":"e_1_2_7_33_1","volume-title":"Handbook of Vitamins","author":"Rivlin R. S.","year":"2007"},{"key":"e_1_2_7_34_1","volume-title":"British Pharmacopoeia","year":"2016"},{"key":"e_1_2_7_35_1","volume-title":"Martindale: The Complete Drug Reference","author":"Sweetman S. C.","year":"2009"},{"key":"e_1_2_7_36_1","volume-title":"Flavins: Photochemistry and Photobiology","author":"Ahmad I.","year":"2006"},{"key":"e_1_2_7_37_1","volume-title":"Advances in Medicine and Biology","author":"Anwar Z.","year":"2017"},{"key":"e_1_2_7_38_1","unstructured":"I.Ahmad Ph. D. thesis University of London London 1968."},{"key":"e_1_2_7_39_1","doi-asserted-by":"publisher","DOI":"10.1016\/S1011-1344(01)00134-8"},{"key":"e_1_2_7_40_1","doi-asserted-by":"publisher","DOI":"10.1021\/jp037048u"},{"key":"e_1_2_7_41_1","doi-asserted-by":"publisher","DOI":"10.1016\/0731-7085(90)80029-O"},{"key":"e_1_2_7_42_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1751-1097.1967.tb08796.x"},{"key":"e_1_2_7_43_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja01583a035"},{"key":"e_1_2_7_44_1","doi-asserted-by":"publisher","DOI":"10.1021\/jo01292a040"},{"key":"e_1_2_7_45_1","first-page":"518","volume":"235","author":"Hatchard C. G.","year":"1956","journal-title":"Proc. Natl. Acad. Sci."},{"key":"e_1_2_7_46_1","volume-title":"Validation of Analytical Procedures: Text and Methodology Q2 (R1)","author":"ICH Harmonised Tripartite Guideline","year":"2005"},{"key":"e_1_2_7_47_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja00903a051"},{"key":"e_1_2_7_48_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0021-9673(01)82399-2"},{"key":"e_1_2_7_49_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja00740a031"},{"key":"e_1_2_7_50_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijpharm.2004.05.020"},{"key":"e_1_2_7_51_1","doi-asserted-by":"publisher","DOI":"10.1039\/b602917e"},{"key":"e_1_2_7_52_1","doi-asserted-by":"publisher","DOI":"10.1208\/s12249-015-0304-2"},{"key":"e_1_2_7_53_1","doi-asserted-by":"publisher","DOI":"10.1002\/cber.19340670539"},{"key":"e_1_2_7_54_1","doi-asserted-by":"publisher","DOI":"10.1016\/0006-3002(60)91518-3"},{"key":"e_1_2_7_55_1","first-page":"451","volume":"33","author":"Hemmerich P.","year":"1976","journal-title":"Fortschr. Chem. Org. Naturst."}],"container-title":["Luminescence"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fbio.3510","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/analyticalsciencejournals.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/bio.3510","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,8]],"date-time":"2025-10-08T18:02:08Z","timestamp":1759946528000},"score":1,"resource":{"primary":{"URL":"https:\/\/analyticalsciencejournals.onlinelibrary.wiley.com\/doi\/10.1002\/bio.3510"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,7,8]]},"references-count":54,"journal-issue":{"issue":"6","published-print":{"date-parts":[[2018,9]]}},"alternative-id":["10.1002\/bio.3510"],"URL":"https:\/\/doi.org\/10.1002\/bio.3510","archive":["Portico"],"relation":{},"ISSN":["1522-7235","1522-7243"],"issn-type":[{"value":"1522-7235","type":"print"},{"value":"1522-7243","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,7,8]]},"assertion":[{"value":"2017-12-06","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2018-05-03","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2018-07-08","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}