Printable Ultrathin Metal Oxide Semiconductor-Based Conformal Biosensors

Area of Science:

• Materials Science
• Bioelectronics
• Nanotechnology

Background:

• Conformal bioelectronics are crucial for advanced wearable and noninvasive health monitoring systems.
• Developing sensitive and reliable biosensors with mechanical flexibility is essential for seamless integration with the human body.

Purpose of the Study:

• To demonstrate a facile method for producing thin, sensitive indium oxide (In2O3)-based conformal biosensors using solution-based processing.
• To evaluate the performance and conformability of these biosensors on complex surfaces.

Main Methods:

• Fabrication of ultrathin (3.5 nm), high-density In2O3 films via one-step aqueous solution coating.
• Integration of In2O3 films onto ultrathin polyimide for conformal biosensor development.
• Functionalization of In2O3 field-effect transistors with self-assembled monolayers for pH sensing and glucose oxidase for d-glucose detection.

Main Results:

• Achieved uniform In2O3 films over large areas with excellent device performance and low mechanical stress.
• Demonstrated highly conformal contact on complex curvilinear surfaces like artificial skin and an artificial eye.
• Successfully detected pH and physiologically relevant levels of d-glucose, showcasing sensor functionality.

Conclusions:

• The developed In2O3-based conformal field-effect transistor biosensors offer a promising platform for wearable health monitoring.
• The facile solution-based processing enables scalable production for future human technology applications.
• These biosensors represent a significant advancement in noninvasive, continuous health-tracking technologies.