Multifunctional IrOx Neural Probe for In Situ Dynamic Brain Hypoxia Evaluation

Area of Science:

• Neuroscience
• Biomedical Engineering
• Materials Science

Background:

• Perioperative cerebral hypoxia and neonatal hypoxia-ischemic encephalopathy cause brain dysfunction.
• Pathogenesis involves neural activity and microenvironment pH, requiring advanced in situ monitoring.
• Existing pH sensors lack multi-modal, multi-channel, and high-resolution capabilities.

Purpose of the Study:

• To develop a multifunctional implantable neural probe for simultaneous electrophysiology recording, pH sensing, and neural stimulation.
• To evaluate the probe's performance for real-time dynamic brain hypoxia assessment.
• To investigate the probe's long-term stability, spatial resolution, and cytotoxicity.

Main Methods:

• Fabrication of a multifunctional implantable iridium oxide (IrOx) neural probe (MIIONP).
• Modification with IrOx films for enhanced recording, stimulation, and pH sensing.
• In vivo testing in a mouse brain hypoxia model for synchronous signal acquisition.

Main Results:

• The IrOx-modified probe demonstrated excellent electrophysiology recording and neural stimulation performance.
• Achieved stable, high-resolution (approx. 100 μm) in situ pH sensing over 4 weeks.
• Successfully captured real-time synchronous changes in brain pH and neural firing in a hypoxia model.

Conclusions:

• The MIIONP enables simultaneous multi-modal physiological signal acquisition in the brain.
• This technology offers valuable applications for real-time dynamic brain disease evaluation.
• The probe shows promise for advancing the understanding and diagnosis of brain hypoxia-related conditions.