Neural Interfaces towards a Treatment of Epilepsy – Merging Photopharmacology with Implantable Optoelectronics and Electrophoretic Drug Delivery

• Applicant: Dr. Johannes Gurke
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering ; Biological and Biomimetic Chemistry ; Cognitive, Systems and Behavioural Neurobiology
• Term: from 2019 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 427938672

• Final Report Year: 2022

Final Report Abstract

The project led to an implant, which is inserted into a rat’s brain. There, it records the local neurological activity, triggers a seizure-like event by electrical stimulation, and administers a drug locally. Further, a light source, emitting two colours of light, has been integrated to control a photoparmacological agent. Using the two colours this so-called photodrug can be activated and deactivated, which has been shown in past studies using brain slices of a mice. Here, the developed implant was used to deliver such a photodrug into the brain of a rat and the drug’s supressing activity was controlled by light. One colour “switches the drug off” where the other “switches the drug on”. The gathered results indicate that an intentionally induced seizure-like event did or didn’t occur in dependence of the colour of the illuminated light. In future that might led to a personalized treatment of epilepsy, where the dose can be tailored to the extent of the occurring seizure. The device has been evaluated about its robustness, long-term stability, and impact on the animal’s health. These experiments showed good performance in the latter two categories. The robustness requires further improvement, especially in the drug delivery system. However, it can be stated that all requirements are fulfilled to proceed with the development. All animal experiments were carried out in accordance with the UK Animals-Scientific Procedures Act (ASPA) 1986. To fabricate the device, a novel approach has been developed during the project, which was not its original objective. The process made use of computer-aided design and manufacturing (CAD+M) in combination with classic microfabrication. Thereby, the strength of both has been combined, namely the flexibility of CAD+M and the high precision of microfabrication. This novel hybrid fabrication process has been published in the journal Materials Horizons.

Publications

• Conducting Polymer-Ionic Liquid Electrode Arrays for High-Density Surface Electromyography. Adv. Healthcare Mater. 2021, 10, 2100374
  Santiago Velasco-Bosom, Nuzli Karam, Alejandro Carnicer-Lombarte, Johannes Gurke, Nerea Casado, Liliana C. Tomé, David Mecerreyes, George G. Malliaras
  
• Microelectrode Arrays for Simultaneous Electrophysiology and Advanced Optical Microscopy. Adv. Sci. 2021, 8, 2004434
  Middya, S., Curto, V. F., Fernández-Villegas, A., Robbins, M., Gurke, J., Moonen, E. J. M., Kaminski, G. S., Malliaras, G. G.
  
• Mater. Horiz., 2022,9, 1727-1734
  J. Gurke, et al.