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Skin-interfaced wearable systems with integrated microfluidic structures and sensing capabilities offer powerful platforms for monitoring the signals arising from natural physiological processes. This paper introduces a set of strategies, processing approaches, and microfluidic designs that harness recent advances in additive manufacturing [three-dimensional (3D) printing] to establish a unique class of epidermal microfluidic (“epifluidic”) devices. A 3D printed epifluidic platform, called a “sweatainer,” demonstrates the potential of a true 3D design space for microfluidics through the fabrication of fluidic components with previously inaccessible complex architectures. These concepts support integration of colorimetric assays to facilitate in situ biomarker analysis operating in a mode analogous to traditional epifluidic systems. The sweatainer system enables a new mode of sweat collection, termed multidraw, which facilitates the collection of multiple, independent sweat samples for either on-body or external analysis. Field studies of the sweatainer system demonstrate the practical potential of these concepts.
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This content will become publicly available on January 2, 2026
Geometrical Modifications for Reliable 3D Printing of Microvalves in Multi-Plane Microfluidic Devices
Three-dimensional (3D) printing has emerged as a transformative technology for fabricating complex microfluidic devices, enabling features that were previously unattainable with traditional layer-by-layer soft lithography. One key challenge in advancing 3D-printed microfluidics is the integration of functional microvalves across multiple spatial orientations. This study explores the design, simulation, and experimental realization of novel microvalve configurations to overcome the limitations of conventional, single-plane valves. We hypothesize that non-traditional valve orientations, such as those with vertically printed membranes or perpendicular control channels, present unique fabrication and operational challenges, including membrane delamination and stress-induced failure. To address these issues, we developed optimized geometries and fabrication techniques, supported by computational fluid dynamics (CFD) simulations to predict and mitigate stress concentrations. Our results demonstrate successful implementation of previously unreported valve configurations, validated through pressure testing and flow control experiments. These advancements expand the versatility of 3D-printed microfluidic systems, paving the way for more robust and adaptable devices in biomedical, chemical, and environmental applications.
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- Award ID(s):
- 2141029
- PAR ID:
- 10574710
- Publisher / Repository:
- engrxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- New Jersey Institute of Technology
- Sponsoring Org:
- National Science Foundation
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