Sensor arrangement based on the silkworm protein fibroin to support transplantation processes (SensoFib)

• Applicant: Professor Dr. Michael J. Schöning
• Subject Area: Biomedical Systems Technology ; Medical Physics, Biomedical Technology ; Measurement Systems
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 548199022

Microvascular flap transplantation is one of the most complex, costly and frequently performed plastic surgery operations. In many cases, however, the blood supply to the graft fails within the first 72 hours, so close monitoring is required. However, the methods typically used are sometimes very subjective and require extensive clinical experience and trained medical staff. Nevertheless, tissue graft loss occurs in up to 8% of cases, which is why more objective monitoring methods are needed. This project therefore aims to develop a sensor array that is positioned between the flap graft and the original defect and is intended to determine relevant parameters (temperature, impedance and partial pressure of oxygen (pO2)) for the graft survival rate. The implanted sensor array must be biocompatible and biodegradable in order to prevent follow-up operations. The biohybrid, implantable sensor array uses bio-based, biocompatible, biodegradable silk fibroin as a flexible and at the same time mechanically resilient carrier film (substrate material) for the sensor chip. This should integrate various electrode arrangements (meander-type, interdigital, and circular electrodes), which are produced using thin- and thick-film technologies from magnesium (for impedance/temperature measurement) or carbon paste (pO2 measurement). Silk fibroin is a protein that is extracted from the cocoon of the silkworm Bombyx mori by the application partner Fibrothelium GmbH; it is to be further optimized in terms of its degradation properties as part of the project. The bioresorbable magnesium, for the conductive electrode structures, shows comparable properties and is provided by the application partner Meotec GmbH. Within this project, the sensor concepts are implemented as a sensor array, where the properties of the components are adapted and optimized for the application purpose in close cooperation with the application partners. The individual sensor readings are combined into a feature combination model, which enables individual, personalized monitoring of the functionality of the transplant. Furthermore, novel passivation/encapsulation materials are being established to optimize the life-time of the sensor array. In addition, bio-compatibility and biodegradability studies are being carried out.

• DFG Programme: Research Grants (Transfer Project)
• Application Partner: Fibrothelium GmbH; Meotec GmbH