Drug-Loaded Hydrogel Microelectrode Arrays Significantly Boost Brain-Computer Interface Performance：Study

The“Micro-Nano Sensing Technology” creative research group of NSFC from the Aerospace Information Research Institute (AIR) of the Chinese Academy of Sciences, led by Professor CAI Xinxia, has made a breakthrough in brain-computer interface technology. The team developed a novel drug-loaded hydrogel-coated microelectrode array (MEA), which allows for long-term, high-quality detection of neural activity. The study was published in the journal Biosensors and Bioelectronics.

Traditional MEA often cause inflammation in the brain due to mechanical differences between the stiff electrode and the soft brain tissue. This can lead to glial scar formation that affects electrode stability and signal quality. This problem limits how well these devices can be used for long-term neural monitoring and treating neurological disorders.

To solve this, the research team designed a hydrogel coating using calcium alginate and chitosan, which is loaded with an anti-inflammatory drug called dexamethasone sodium phosphate. The MEA was further optimized by integrating various conductive nanomaterials to enhance the electrical performance. The hydrogel coating makes the electrode more compatible with brain tissue and actively releases the drug, reducing inflammation, and increasing the stability and lifespan of the electrodes.

Tests in animals showed that the modified MEA exhibited outstanding performance. The electrical properties they detected were clearer and more reliable over long periods. The electrodes were also able to detect dopamine, an important neurotransmitter, with high sensitivity. The technology allowed for detailed recording of neural activities, revealing differences in how neurons behave during various states, such as anesthesia and wakefulness.

This new drug-loaded hydrogel, serving as a highly effective nanobiointerface and drug delivery carrier, shows great potential for long-term neural monitoring. It is expected to enhance the performance and acceptance of brain-machine interface devices in medical practice. This innovation also holds significant promise for neuroscience research and developing new treatments for neurological diseases.

Schematic diagram of dual-mode detection using a MEA modified with hydrogel. (Image by AIR)