In vivo validation of a mechanically adaptive microfluidic intracortical device as a platform for sustained local drug delivery

Introduction: Intracortical microelectrodes (IME) are vital to properly functioning brain-computer interfacing (BCI). However, the recording electrodes have shown a steady decline in performance after implantation, mainly due to chronic inflammation. Compliant materials have been explored to decrease differential strain resulting in lower neural inflammation. We have previously developed a fabrication method for creating mechanically adaptive microfluidic probes made of a cellulose nanocrystal (CNC) polymer nanocomposite material that can become compliant after implantation. Here, we hypothesized that our device, would have a similar tissue response to the industry standard, allowing drug delivery therapeutics to improve neural inflammation in the future. Methods: RNA expression analysis was performed to determine the extent of neural inflammation and oxidative stress in response to the device compared to controls and to naïve shame tissue. Results: Results presented for both four- and eight-weeks post-implantations suggest that our device offers a promising platform technology that can be used to deliver therapeutic strategies to improve IME performance.