Microfluidic Glass-Elastomer Membrane (GEM) Oxygenator

• Christopher Collier, Biomedical Engineering, University of Delaware

• David Blauvelt, Nemours, Nemours Childrens Health

Extracorporeal membrane oxygenation (ECMO) provides critical gas exchange support for patients ranging from premature infants to adults with respiratory failure. Current hollow fiber oxygenators require large priming volumes and extensive anticoagulation due to poorly controlled blood flow dynamics. This project develops a next-generation microfluidic Glass-Elastomer Membrane (GEM) oxygenator using a flat-plate PDMS-coated glass membrane, designed to improve gas exchange efficiency, reduce priming volume, and enable precise control of blood flow. This work focused on two major engineering advances in device assembly: flow cell sealing and manifold sealing. The flow cell transitioned from an epoxy-bonded, externally clamped design to a mechanically fastened assembly using a machined Viton cord seal and torque-controlled screws. Torque optimization identified 80 cN·m as the validated assembly parameter, producing a mean channel height of 144 µm — within the target range of 125–175 µm — establishing a reproducible, quantifiable relationship between assembly torque and device geometry. The distribution manifold was redesigned across three iterations, progressing from an unsealed connection to adhesive-bonded grooves, and finally to a combined groove-and-O-ring face seal at each channel port. Manifold and mock flow cell assemblies were evaluated using pressure hold and dye perfusion testing, with the current design holding 30 psi for four minutes before leak detection. Together, these engineering improvements establish a reproducible, mechanically verifiable assembly process that supports scaling toward a full 32-channel oxygenator. Future work includes further sealing refinement, translation to a clinical-scale device, and evaluation of gas exchange and hemocompatibility performance.