Combined surface-sensitive microscopies analyze tissue damaged by neural devices

Implantable neural technologies are used to study brain health and neural activity throughout a wide variety of medical applications. To maintain successful, long-term operation, these devices must have long-term stability. This can be impeded by adverse side effects such as inflammation, chemical instability, technical difficulties and rejection due to foreign body response.

De Carvalho et al. used three combined surface sensitive microscopies to study the health of tissue after implantation of a neural device. Their study was performed on non-human primates and specifically examined inflammation after implantation and how to reduce it.

The authors believe by monitoring the causes of inflammation with combined time-of-flight secondary ion mass spectrometry, x-ray photoelectron spectroscopy and x-ray photoemission electron microscopy, they can improve the development of implantable devices.

“The combination of these microscopies allowed us to identify important chemically distinct regions on tissue, highlighting the main chemical species present, as well as to quantify the surface composition in each region identified,” said author Amanda De Carvalho.

Using this approach, the authors successfully characterized the surface of biological tissue which had been in contact with the neural devices. They observed signs of severe inflammation and early necrosis of the tissue.

“The next step is to include scanning probe microscopies for the topographic study of the same tissue sections that were analyzed using these microscopies,” said De Carvalho. “Beside analysis of the fibrous tissue formed around a neural device, other biological systems will be studied using this approach.”

Source: “Combining surface-sensitive microscopies for analysis of biological tissues after neural device implantation,” by Amanda Gomes De Carvalho, Jean-Paul Barnes, Olivier Renault, Denis Mariolle, Christophe Gaude, David Ratel, and Anouk Galtayries, Biointerphases (2020). The article can be accessed at https://doi.org/10.1116/6.0000110 .