On-Demand Contact-Mode Switchable Cerebral Cortex Biosensors Enhanced by Magnetic Actuation

Area of Science:

• Bioelectronics
• Materials Science
• Nanotechnology

Background:

• Nanomaterial-based field-effect transistors (nano-FETs) are crucial for biosensing but their performance depends on metal-semiconductor interfaces.
• Piezotronic effect offers interface regulation but has limitations, especially in vivo.
• Existing methods lack remote control and adaptability for complex biological environments.

Purpose of the Study:

• To develop a magnetically controllable piezoelectric device (MCPD) for remote and precise regulation of nano-FET interfaces.
• To enhance the sensitivity of biomolecule detection and neural signal recording using the MCPD.
• To create a biocompatible and minimally invasive neural electrode system.

Main Methods:

• Integration of piezoelectric nano-FET biosensors with magnetic soft robot principles.
• Utilizing magnetic field (MF)-induced piezotronic effect for modulating metal-semiconductor interfaces.
• Designing a device capable of reversible state transitions (flat to bent) under MF control.

Main Results:

• The MCPD demonstrated remote, precise, and stable modulation of interfacial properties.
• Enhanced sensitivity was achieved for dopamine detection and neural impulse recording.
• The device showed a reversible morphological transition within seconds upon MF application.
• The MCPD's structure enables semi-invasive neural electrodes with improved biocompatibility.

Conclusions:

• The MCPD offers a novel approach for remote regulation of piezoelectric devices via magnetic fields.
• This technology expands applications for nano-FETs in bioelectronics, including implanted neural interfaces.
• The study presents a potential strategy for activating implantable piezoelectric materials in a controlled manner.