Fluorescence Quenching and Electron Transfer Dynamics of a Thiophene-Substituted 1,3,4-Oxadiazole Derivative with Nitroaromatic Compounds

Fluorescence Quenching and Electron Transfer Dynamics of a Thiophene-Substituted 1,3,4-Oxadiazole Derivative with Nitroaromatic Compounds | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Fluorescence Quenching and Electron Transfer Dynamics of a Thiophene-Substituted 1,3,4-Oxadiazole Derivative with Nitroaromatic Compounds Praveenakumara A Valmiki, Thippeswamy. M. S, Lohit Naik, C. V. Maridevarmath, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6239689/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 May, 2025 Read the published version in Journal of Fluorescence → Version 1 posted 15 You are reading this latest preprint version Abstract This study investigates the fluorescence quenching behavior of a newly synthesized thiophene-substituted 1,3,4-oxadiazole derivative, 2-(4-(4-vinylphenyl)phenyl)-5-(5-(4-vinylphenyl)thiophene-2-yl)-1,3,4-oxadiazole (TSO), in the presence of various nitroaromatic compounds (NACs), including 2-nitrotoluene, 4-nitrotoluene, nitrobenzene, and picric acid (2,4,6-trinitrophenol). The interactions were examined in an ethanol medium at room temperature using steady-state and time-resolved fluorescence spectroscopy. Steady-state fluorescence analysis revealed a non-linear Stern-Volmer (SV) plot exhibiting positive deviation, while time-resolved measurements displayed a linear relationship. To interpret these findings, ground-state complex formation and the sphere-of-action static quenching models were applied. The study determined key quenching parameters, including the Stern-Volmer constant, quenching rate constant, static quenching constant, and sphere-of-action radius. Notably, fluorescence quenching efficiency increased with the number of NO₂ groups in the NACs.Electrochemical analysis, complemented by Density Functional Theory (DFT) calculations, confirmed that electron transfer was the primary quenching mechanism. Furthermore, binding site analysis demonstrated a 1:1 binding stoichiometry between TSO and NACs, with picric acid exhibiting the highest binding affinity. Given the growing interest in fluorescence-based sensing approaches, these findings contribute valuable insights into the development of advanced sensors for detecting nitroaromatic pollutants and explosive residues. Fluorescence Quenching Stern-Volmer Plot Nitro Aromatic Compounds DFT Thermodynamic Parameters Full Text Additional Declarations No competing interests reported. Supplementary Files Suplimentaryfile.docx Cite Share Download PDF Status: Published Journal Publication published 02 May, 2025 Read the published version in Journal of Fluorescence → Version 1 posted Editorial decision: Revision requested 31 Mar, 2025 Reviews received at journal 28 Mar, 2025 Reviews received at journal 27 Mar, 2025 Reviews received at journal 27 Mar, 2025 Reviewers agreed at journal 27 Mar, 2025 Reviewers agreed at journal 24 Mar, 2025 Reviews received at journal 23 Mar, 2025 Reviewers agreed at journal 21 Mar, 2025 Reviewers agreed at journal 21 Mar, 2025 Reviewers agreed at journal 21 Mar, 2025 Reviewers agreed at journal 21 Mar, 2025 Reviewers invited by journal 21 Mar, 2025 Editor assigned by journal 19 Mar, 2025 Submission checks completed at journal 19 Mar, 2025 First submitted to journal 16 Mar, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6239689","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":435504373,"identity":"2f961ceb-a1dc-4619-8b84-a8a0904ed2c1","order_by":0,"name":"Praveenakumara A Valmiki","email":"","orcid":"","institution":"Karnatak Science College","correspondingAuthor":false,"prefix":"","firstName":"Praveenakumara","middleName":"A","lastName":"Valmiki","suffix":""},{"id":435504374,"identity":"b62368de-f467-41b2-80df-f8c0894b776b","order_by":1,"name":"Thippeswamy. M. 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Given the growing interest in fluorescence-based sensing approaches, these findings contribute valuable insights into the development of advanced sensors for detecting nitroaromatic pollutants and explosive residues.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e","manuscriptTitle":"Fluorescence Quenching and Electron Transfer Dynamics of a Thiophene-Substituted 1,3,4-Oxadiazole Derivative with Nitroaromatic Compounds","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-31 04:44:15","doi":"10.21203/rs.3.rs-6239689/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-03-31T12:13:09+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-03-28T18:35:12+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-03-27T15:15:44+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-03-27T05:14:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"260881459023526255304516846438383639827","date":"2025-03-27T04:28:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"141771695241520147470055080263539539046","date":"2025-03-24T08:13:50+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-03-23T08:44:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"167463441553228695353550389002427289329","date":"2025-03-22T03:59:52+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"76088194504788538718605651258721503558","date":"2025-03-22T00:38:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"250092639981521683522013994320324067345","date":"2025-03-21T23:30:22+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"13155352770718786482662804327550911109","date":"2025-03-21T18:37:04+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-03-21T18:33:01+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-19T18:03:51+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-03-19T18:02:56+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Fluorescence","date":"2025-03-16T22:49:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-fluorescence","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jofl","sideBox":"Learn more about [Journal of Fluorescence](https://www.springer.com/journal/10895)","snPcode":"10895","submissionUrl":"https://submission.nature.com/new-submission/10895/3","title":"Journal of Fluorescence","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"e1e9c6ae-55cd-444a-a84e-3df9345d6146","owner":[],"postedDate":"March 31st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-05-05T16:00:32+00:00","versionOfRecord":{"articleIdentity":"rs-6239689","link":"https://doi.org/10.1007/s10895-025-04333-8","journal":{"identity":"journal-of-fluorescence","isVorOnly":false,"title":"Journal of Fluorescence"},"publishedOn":"2025-05-02 15:57:03","publishedOnDateReadable":"May 2nd, 2025"},"versionCreatedAt":"2025-03-31 04:44:15","video":"","vorDoi":"10.1007/s10895-025-04333-8","vorDoiUrl":"https://doi.org/10.1007/s10895-025-04333-8","workflowStages":[]},"version":"v1","identity":"rs-6239689","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6239689","identity":"rs-6239689","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}