In lab, 3D-printed membranes raise artificial-lung oxygen transfer by up to 88%

At Hannover Medical School, Prof. Dr Bettina Wiegmann’s team has developed a membrane architecture printed as a continuous three-dimensional network as an alternative to the bundles of tiny plastic tubes used in artificial-lung systems. The new design transferred up to 88% more oxygen than conventional hollow-fibre membranes in the team’s study, published in Advanced Materials.

The work is part of a research programme on an implantable lung led by Wiegmann, an emergency medicine specialist and consultant in cardiac surgery at Hannover Medical School. Researchers from RWTH Aachen University worked with her group at the Lower Saxony Centre for Biomedical Engineering, Implant Research and Development. The starting point is ECMO — extracorporeal membrane oxygenation, a system already used clinically to pass blood across artificial membranes for gas exchange.

Those conventional membranes resemble parallel rows of tiny straws. Blood flow is not distributed ideally through the bundles, which limits gas exchange and creates interfaces where clots can form. The new TPMS — triply periodic minimal surface — architecture creates one connected network instead, spreading blood more evenly and reducing flow resistance. Its large surface area can fit into a smaller volume, while 3D printing allows the structure to be produced and customised precisely.

The membrane is made from a silicone polymer that the researchers describe as biocompatible, non-toxic and chemically stable. It is permeable to oxygen and carbon dioxide and can be colonised by endothelial cells, the cells that line natural blood vessels and can help regulate clotting. That could improve how future artificial lungs interact with blood, although the published result does not establish long-term performance in patients.

So what changes in practice? In the nearer term, the architecture could make existing ECMO systems more efficient and compact, potentially offering the same or better oxygen supply in a smaller artificial lung. The longer-term plan is more ambitious: use a patient’s CT scan to create a mould for individually tailored lung segments or an entire lung, then seed the printed structure with the patient’s own or genetically modified endothelial cells. That implantable biohybrid lung is still a research goal, not a deployed device.