Integrated Hydrogel Optical Fiber Electronics with Mechanically Robust Interfaces Enable Simultaneous...

Area of Science:

• Neural bioelectronics
• Biomaterials science
• Neuroscience engineering

Background:

• Hydrogel-based electrodes and optical guides are key for neural bioelectronics due to their compliance and hydration.
• Integrating multiple hydrogel functionalities in one device is difficult because of material compatibility and interfacial issues.

Purpose of the Study:

• To develop an integrated hydrogel optical fiber electronics (iHOFE) platform.
• To enable concurrent electrical and optical neural interfacing within a single device.

Main Methods:

• Fabrication of a multilayer hydrogel structure with an optical core, conductive layer, and insulating sheath.
• Engineering robust interfaces between hydrogel layers using chemical bonding and topological entanglement.
• Testing the platform's performance through long-term (two-month) hippocampal implantation in vivo.

Main Results:

• Demonstrated a stable, multilayer hydrogel device capable of concurrent electrical and optical operation under mechanical stress.
• Achieved high-fidelity electrophysiological recording and optogenetic modulation in the same neural region.
• Validated the platform's long-term efficacy and biocompatibility in vivo.

Conclusions:

• The iHOFE platform successfully integrates electrical and optical functionalities for neural interfacing.
• This technology advances the development of multifunctional neural bioelectronics for deep neural circuit interrogation and manipulation.
• The engineered interfaces and material design overcome previous limitations in multimodal hydrogel device integration.