Anti-biofouling PCL-based Polyurethane Permselective Film Packaging for Dopamine-sensing Brain Implant

In vivo dopamine measurement can be realized using an implantable sensor employing an electrochemical method. However, due to the brain's physiological environment comprising multiple substances, such as neurotransmitters, lipids, proteins, and other chemical substances, sensing electrodes often suffer in biofouling and selectivity issues. Therefore, this sensor requires a filter or a coating to prevent both, the biofouling and at the same time stop the other chemical substance attachment to the sensor. This filter can be in the form of packaging which can protect the entire brain implant. Polycaprolactone (PCL)-based polyurethane (PU) is a biodegradable bioinert polymer that has been widely used in long-term implants. A packaging made of polyurethane film can prevent biofilm formation on the implant due to its antibacterial properties. Furthermore, it also acts as a permselective membrane that can filter ascorbic and uric acid due to its porous structure. This packaging can also prevent electrode fouling by preventing non-electroactive species such as lactose, sucrose, and urea. © 2024 NordPac 2024 - 60th Annual Microelectronics and Packaging Conference and Exhibition. All rights reserved.