Influence of Mass Transport Near Parallel Band Pumping Electrodes and Walls on the Fate of Chemical Species in a Sample Plug Introduced onto a Redox Magnetohydrodynamics Microfluidics Chip

Influence of Mass Transport Near Parallel Band Pumping Electrodes and Walls on the Fate of Chemical Species in a Sample Plug Introduced onto a Redox Magnetohydrodynamics Microfluidics Chip | 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 Influence of Mass Transport Near Parallel Band Pumping Electrodes and Walls on the Fate of Chemical Species in a Sample Plug Introduced onto a Redox Magnetohydrodynamics Microfluidics Chip Shirin Hesan, Jörg König, Foysal Z. Khan, Christian Cierpka, Ingrid Fritsch This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8800224/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 23 You are reading this latest preprint version Abstract A 3D finite element model is used to investigate the behavior of a small sample volume of molecules inside a redox-magnetohydrodynamics (R-MHD) microfluidic chamber (3.0 cm × 1.7 cm, 429 µm-high), enclosing chip-based, coplanar parallel-band electrodes ( ~ 900 µm wide, 1.5 cm long, and 28 µm thick). A 539-pL cylindrical sample plug is introduced, 20 µm radius, spanning the chamber height, containing 0.10 M molecular species with diffusion coefficient of 8.75 × 10⁻¹⁰ m²·s⁻¹. Fluid motion is driven by the magnetic portion of the Lorentz force by applying ± 400 µA between two pumping electrode pairs, separated by 2760 µm and 4441 µm, and positioned above a 0.37 T permanent magnet. The model tracks how plug trajectory, spreading, and deformation under the combined influence of molecular diffusion and R-MHD-driven convection depends on electrode configuration, pumping direction, wall placement and initial plug position. Different scenarios include transporting the plug toward a chamber wall and sending it around electrode ends while maintaining a closed circulating zone rather than reaching chamber boundaries. The findings demonstrate that sample plugs can be steered, retained, or redirected through electrode activation and current polarity, without external pumps or moving parts, enabling programmable sample manipulation for R-MHD-based lab-on-a-chip systems. Full Text Additional Declarations Competing interest reported. I. Fritsch and F. Z. Khan declare a potential conflict of interest as they are listed as inventors on a patent filed by the Board of Trustees of the University of Arkansas concerning MHD technologies and methods. The other authors declare no conflict of interest. Supplementary Files SHFeb20Paper2SIfinalresubmittedx3.docx Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 30 Mar, 2026 Reviews received at journal 29 Mar, 2026 Reviews received at journal 27 Mar, 2026 Reviews received at journal 26 Mar, 2026 Reviews received at journal 25 Mar, 2026 Reviews received at journal 23 Mar, 2026 Reviewers agreed at journal 23 Mar, 2026 Reviews received at journal 22 Mar, 2026 Reviewers agreed at journal 22 Mar, 2026 Reviewers agreed at journal 18 Mar, 2026 Reviewers agreed at journal 18 Mar, 2026 Reviewers agreed at journal 18 Mar, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviews received at journal 17 Mar, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviewers invited by journal 17 Mar, 2026 Editor invited by journal 24 Feb, 2026 Editor assigned by journal 21 Feb, 2026 Submission checks completed at journal 21 Feb, 2026 First submitted to journal 20 Feb, 2026 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-8800224","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":608440899,"identity":"52808eba-d2c1-45f4-814d-56d8dac80d8e","order_by":0,"name":"Shirin Hesan","email":"","orcid":"","institution":"University of Arkansas at Fayetteville","correspondingAuthor":false,"prefix":"","firstName":"Shirin","middleName":"","lastName":"Hesan","suffix":""},{"id":608440904,"identity":"df3156f9-4847-4871-9b97-4840589413b2","order_by":1,"name":"Jörg König","email":"","orcid":"","institution":"Ilmenau University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Jörg","middleName":"","lastName":"König","suffix":""},{"id":608440905,"identity":"3eb6813a-f747-46a2-bd6e-5edbfef5c628","order_by":2,"name":"Foysal Z. 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