3D-Printed TPMS Membranes Could Make Artificial Lungs 88% More Efficient

Why ECMO lungs hit a ceiling

When a patient's lungs fail, extracorporeal membrane oxygenation, or ECMO, buys time. Blood flows past plastic hollow-fiber membranes that swap CO2 for oxygen the way a healthy lung would. The catch is those membranes limit gas exchange, create uneven blood flow, and encourage clotting. Patients can stay on ECMO only so long before the artificial surfaces become a liability.

A team led by Prof. Dr. Bettina Wiegmann at Hannover Medical School has spent years tackling that problem. Working with researchers at RWTH Aachen University and published this month in Advanced Materials, they replaced the hollow-fiber bundle with a 3D-printed architecture based on triply periodic minimal surfaces, or TPMS.

What TPMS changes

Instead of parallel straws, the new design forms a continuous three-dimensional network. Blood spreads more evenly across the surface. The structure mimics the alveolar geometry of a real lung: maximum surface area in minimum volume. The team reports up to 88% higher oxygen transfer compared with conventional hollow-fiber membranes, while using less overall device volume.

The material is a biocompatible silicone polymer. It passes oxygen and carbon dioxide freely and can be colonized by endothelial cells, the same cells that line blood vessels and regulate clotting. That could make the membrane friendlier to blood over long runs.

Where this actually goes

The immediate payoff is smaller, more efficient ECMO systems. A machine that does more work in a smaller package matters in transport and in ICUs where space is tight. Longer term, the team wants to print patient-specific lung segments from CT scans, seed them with the patient's own cells, and implant them as a bridge or replacement for donor lungs.

Donor lungs remain scarce. If a 3D-printed membrane architecture can buy more time today and lay groundwork for implantable biohybrid lungs tomorrow, that is real progress.