{"title":"Characterization of hydrogel-induced flow control in paper-based microfluidics platform","authors":"Neha Majee, Chandra Bhushan, Debayan Das","doi":"10.1007/s10404-025-02832-5","DOIUrl":null,"url":null,"abstract":"<div><p>Paper-based microfluidic platforms are widely utilized in point-of-care (POC) diagnostics, filtration, and fluid handling due to their cost-effectiveness and simplicity. However, uncontrolled capillary-driven transport often results in performance inconsistencies, compromising sensitivity, specificity, and reproducibility. Hydrogel-infused paper matrices present a promising strategy to regulate fluid flow by modifying the porous microstructure, though their impact on transport dynamics remains insufficiently explored. This study investigates the role of hydrogel concentration and fluid viscosity in controlling flow behavior in paper membranes, relevant to diagnostics applications. Hydrogel is pre-imbibed into paper assays to modulate capillary transport, and the effects of varying injected fluid viscosities (0.954–1.54 cP, corresponding to solute concentrations of 0.055–0.555 M) and hydrogel concentrations (4.83–8.06 mg/mL) are examined across three distinct porous substrates. Real-time, high-resolution imaging enables quantitative analysis of fluid front evolution, including angular deviations, length variations, and interface curvature. Hydrogel presence increases flow resistance by 3-33.5%, while early-stage angular deviations reach up to 500% before stabilizing (reducing by 50-100%). Length deviations initially fluctuate (150-300%) but decline as imbibition progresses. Fluid front curvature also varies significantly (11-64%) in early stages. Viscous fluid enhances flow control, increasing resistance by 11-36% and reducing instability. Additionally, smaller pore sizes are found to improve flow uniformity. These findings offer new insights into hydrogel-mediated microfluidic regulation and pave the way for optimized, reproducible, and high-performance POC diagnostic systems.</p></div>","PeriodicalId":706,"journal":{"name":"Microfluidics and Nanofluidics","volume":"29 8","pages":""},"PeriodicalIF":2.5000,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Microfluidics and Nanofluidics","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s10404-025-02832-5","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"INSTRUMENTS & INSTRUMENTATION","Score":null,"Total":0}
引用次数: 0
Abstract
Paper-based microfluidic platforms are widely utilized in point-of-care (POC) diagnostics, filtration, and fluid handling due to their cost-effectiveness and simplicity. However, uncontrolled capillary-driven transport often results in performance inconsistencies, compromising sensitivity, specificity, and reproducibility. Hydrogel-infused paper matrices present a promising strategy to regulate fluid flow by modifying the porous microstructure, though their impact on transport dynamics remains insufficiently explored. This study investigates the role of hydrogel concentration and fluid viscosity in controlling flow behavior in paper membranes, relevant to diagnostics applications. Hydrogel is pre-imbibed into paper assays to modulate capillary transport, and the effects of varying injected fluid viscosities (0.954–1.54 cP, corresponding to solute concentrations of 0.055–0.555 M) and hydrogel concentrations (4.83–8.06 mg/mL) are examined across three distinct porous substrates. Real-time, high-resolution imaging enables quantitative analysis of fluid front evolution, including angular deviations, length variations, and interface curvature. Hydrogel presence increases flow resistance by 3-33.5%, while early-stage angular deviations reach up to 500% before stabilizing (reducing by 50-100%). Length deviations initially fluctuate (150-300%) but decline as imbibition progresses. Fluid front curvature also varies significantly (11-64%) in early stages. Viscous fluid enhances flow control, increasing resistance by 11-36% and reducing instability. Additionally, smaller pore sizes are found to improve flow uniformity. These findings offer new insights into hydrogel-mediated microfluidic regulation and pave the way for optimized, reproducible, and high-performance POC diagnostic systems.
期刊介绍:
Microfluidics and Nanofluidics is an international peer-reviewed journal that aims to publish papers in all aspects of microfluidics, nanofluidics and lab-on-a-chip science and technology. The objectives of the journal are to (1) provide an overview of the current state of the research and development in microfluidics, nanofluidics and lab-on-a-chip devices, (2) improve the fundamental understanding of microfluidic and nanofluidic phenomena, and (3) discuss applications of microfluidics, nanofluidics and lab-on-a-chip devices. Topics covered in this journal include:
1.000 Fundamental principles of micro- and nanoscale phenomena like,
flow, mass transport and reactions
3.000 Theoretical models and numerical simulation with experimental and/or analytical proof
4.000 Novel measurement & characterization technologies
5.000 Devices (actuators and sensors)
6.000 New unit-operations for dedicated microfluidic platforms
7.000 Lab-on-a-Chip applications
8.000 Microfabrication technologies and materials
Please note, Microfluidics and Nanofluidics does not publish manuscripts studying pure microscale heat transfer since there are many journals that cover this field of research (Journal of Heat Transfer, Journal of Heat and Mass Transfer, Journal of Heat and Fluid Flow, etc.).