For people with severe lung diseases, a lung transplant is often the last resort. However, donor organs are scarce. Until a suitable donor lung becomes available, extracorporeal membrane oxygenation (ECMO) systems can support lung function. Yet their hollow-fiber membrane architecture limits gas exchange, leads to uneven blood flow, and, together with the artificial surfaces, promotes blood clotting. A research team at Hannover Medical School (MHH), led by DZL researcher Prof. Dr. Bettina Wiegmann and in collaboration with RWTH Aachen University, has now developed an entirely new, 3D-printable membrane architecture that could improve both oxygen transfer and blood compatibility.
For people with severe lung diseases, transplantation of a healthy organ is often their only chance of survival. Yet donor lungs are in short supply. A new type of artificial lung could help address this shortage. Since 2017, a team led by Prof. Dr. Bettina Wiegmann, an emergency medicine specialist and cardiac surgeon at the Department of Cardiothoracic, Transplantation and Vascular Surgery at MHH, has been researching this approach as part of the German Research Foundation (DFG) Priority Programme “Towards an Implantable Lung.” Together with her team at the Lower Saxony Centre for Biomedical Engineering, Implant Research and Development (NIFE), she is developing what is known as a biohybrid lung. The technology builds on extracorporeal membrane oxygenation (ECMO), an established clinical lung support system in which blood flows past artificial hollow-fiber membranes (HFMs) that facilitate gas exchange.
The researcher has now taken a major step forward. Together with researchers from RWTH Aachen University, she has developed a novel membrane architecture that enables much more efficient gas exchange. The architecture can be manufactured easily and precisely using 3D printing, achieves significantly higher oxygen transfer, and enables a more compact design. The technology is not only promising for the development of implantable biohybrid lungs. In the future, it could also make conventional ECMO systems more efficient and compact. The study has been published in Advanced Materials, an internationally renowned journal in materials science.
The HFMs used in ECMO resemble tiny straws arranged in parallel. However, this arrangement can create turbulence, resulting in uneven blood flow and limiting the efficiency of gas exchange. In addition, contact between blood and artificial surfaces increases the risk of thrombosis. “With current ECMO systems, we can only support lung function for a limited period of time because blood clots can form when it comes into contact with the artificial surfaces,” explains Prof. Wiegmann. She is therefore pursuing a different approach: a completely new membrane architecture based on so-called triply periodic minimal surfaces (TPMS). Unlike densely packed HFMs, the TPMS structure forms a continuous three-dimensional network. This allows blood to flow more evenly, enabling more efficient gas exchange while also providing the basis for more compact artificial lungs.
Like the alveoli in natural lungs, TPMS structures provide a very large surface area within a small volume. This maximizes the area available for gas exchange while minimizing the space required. The human lungs contain around 100 to 140 square metres of respiratory surface area, densely packed into approximately 300 million alveoli. TPMS structures do not yet match this level of packing density, but they avoid areas of low blood flow and reduce flow resistance. They can also be produced easily and individually using modern 3D printing technology.
“We optimized the TPMS architectures and achieved up to 88% higher oxygen transfer compared with conventional hollow-fiber membranes,” says Prof. Wiegmann. “This means that in the future, the same or even better oxygen supply could potentially be achieved with significantly smaller artificial lungs.”
The material used for the membranes also opens up new possibilities. The TPMS membranes are made from a special silicone polymer that is biocompatible, non-toxic, and chemically stable. At the same time, the material is highly permeable to oxygen and carbon dioxide, which is essential for efficient gas exchange. It can also be seeded with endothelial cells, which line our natural blood vessels and can help regulate blood clotting. This could significantly improve the blood compatibility of future artificial lungs.
The long-term goal of the research is to use computed tomography (CT) images of a damaged lung to create a “blueprint” for 3D printing. This could enable individually tailored artificial lung components—or even entire lungs—to be produced using 3D printing. Once seeded with the patient’s own or genetically modified endothelial cells, these artificial lungs could potentially be implanted and permanently take over lung function.
“However, the new TPMS structure has significant potential even without endothelial cells,” emphasizes Prof. Wiegmann. “It could already make ECMO systems more efficient, compact, and blood-compatible as a replacement for today’s hollow-fiber membranes. In the long term, it could also provide the foundation for implantable biohybrid lungs.”
Prof. Wiegmann now hopes that her work will receive continued support, enabling the implantable biohybrid lung to eventually make its way into clinical practice—initially as a bridge to lung transplantation and, in the long term, as a fully functional organ replacement.
Her international recognition also reflects the significance of her research and expertise. The American Society for Artificial Internal Organs (ASAIO) has selected Prof. Wiegmann for its Inaugural Fellow Class 2026, recognizing her research achievements, international engagement, and contributions to the development of biohybrid organ support systems and extracorporeal therapies. The newly established fellowship honors leading scientists worldwide for outstanding contributions to the development of artificial organs, advanced organ support systems, and innovative translational therapies.
Original publication: Pflaum M, Barbian KP, Neuhaus F, Sitarz G, Nölke C, Jansen SV, Linkhorst J, Hirschwald LT, Brosch S, Certa C, Steinseifer U, Wessling M, Arens J, Ruhparwar A, Wiegmann B. From Fiber Bundles to Architected Membranes: Triply Periodic Minimal Surface Architectures for Biohybrid Artificial Lungs. Adv Mater. 2026 Aug 3:e74361. doi: 10.1002/adma.74361. Epub ahead of print. PMID: 42544733.
Source: BREATH
