Well-defined microapertures for ion channel biosensors.

Area of Science:

• Biophysics
• Materials Science
• Nanotechnology

Background:

• Gated ion channels are biological nanopores that function as sensors, adaptable through protein engineering.
• Reconstituting these channels into synthetic lipid bilayers enables their use in sensory devices.
• Instability of lipid bilayers hinders the integration of ion channels into practical analytical devices.

Purpose of the Study:

• To develop a stable sensory chip for detecting molecules using mechanosensitive ion channels.
• To overcome the limitations of lipid bilayer instability in biosensor applications.

Main Methods:

• Fabrication of a stable Si/SiO(2) chip with a 3 μm pore using lithography and dry etching.
• Functional reconstitution of a mechanosensitive ion channel into the chip's pores.
• Single-channel electrical detection of ion channel activity upon activation.

Main Results:

• A straightforward fabrication strategy for a stable Si/SiO(2) sensory chip was established.
• Mechanosensitive ion channels were successfully integrated into the chip pores, retaining their function.
• Single-channel detection of ion channel activity was achieved, demonstrating the chip's sensitivity.

Conclusions:

• Stable Si/SiO(2) sensory chips with integrated ion channels offer a promising platform for sensitive molecular detection.
• This approach overcomes the instability issues associated with traditional lipid bilayers in biosensors.
• Excitable ion channels in stable nanopores can be utilized as highly sensitive detectors for specific molecules.