OLED platform for photobiomodulation and detection of neuronal activity

• Applicant: Dr. Sabina Hillebrandt
• Subject Area: Biomedical Systems Technology ; Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 564757674

The aim of this project is to extensively investigate the potential of OLED technology in neuroprobes in order to find an innovative therapy option based on photobiomodulation (PBM) and the resulting neuroprotection for the treatment of neurodegenerative diseases such as Parkinson's disease (PD) in the long term. To this end, NIR OLEDs will be integrated on flexible, implantable neuroprobes to test and optimise their suitability for PBM of neurons both in vitro and in vivo. In combination with OLED OPD detectors, this creates a platform for investigating neuronal activity and correlating it with the preservation of neurons through PBM. The work programme is designed to investigate three central hypotheses. The first hypothesis is that OLEDs in the NIR range and OLED/OPD detectors are capable of inducing PBM on the one hand and detecting neuronal activity on the other. Within this hypothesis, it is investigated whether the platform using OLED/OPD detectors in the visible wavelength range enables the monitoring of neuronal activity with already established single components in vitro and in vivo. Furthermore, it will be tested whether NIR OLEDs can achieve a sufficient power density for PBM in neurons. Specifically, NIR OLEDs with emission maxima at 820 nm and above 950 nm with a power density of at least 0.1 mW/mm² are to be developed. The second hypothesis deals with the miniaturisation of components on the micrometre scale and their potential to enable a minimally invasive optical brain-machine interface. It will be tested whether the reduction of the implant size from millimetre to micrometre scale preserves the mechanical stability and functionality of the neuroprobe and its components. At the same time, it is being investigated whether the miniaturised neuroprobe can also be used in the long term under conditions of increased temperature and humidity in the organism. The third hypothesis assumes that PBM with NIR OLEDs can achieve neuroprotective effects on dopaminergic neurones with induced PD. This involves optimising PBM parameters - such as wavelength, power density and frequency - in vitro using the combination of PBM and calcium imaging (OLED/OPD detector) to achieve the maximum neuroprotective effect. In addition, measurable effects of PBM on haemodynamics and thus neuronal activity detected through the OLED/OPD pair will be observed in the PD mouse model, indicating neuroprotection. Finally, it will be tested whether the bidirectional neuroprobe can be successfully applied in the mouse model without significantly impairing neuronal activity or tissue function. By systematically addressing these hypotheses, a significant step towards the development of a novel, minimally invasive treatment method for PD will be taken.

• DFG Programme: Research Grants
• International Connection: Japan
• Cooperation Partner: Professor Dr. Chihaya Adachi
• Co-Investigators: Professor Dr. Martin Fuhrmann; Professor Dr. Malte Gather; Professor Dr. Klaus Meerholz