Integrated contact lens sensor system based on multifunctional ultrathin MoS₂ transistors

Area of Science:

• Materials Science
• Biomedical Engineering
• Nanotechnology

Background:

• Smart contact lenses offer direct physiological and environmental monitoring but often face challenges with sensor efficiency, fabrication, stability, and biocompatibility.
• Existing smart contact lens designs struggle to integrate multiple sensing modalities effectively without compromising mechanical integrity or user comfort.

Purpose of the Study:

• To develop a flexible and multifunctional smart contact lens with an integrated serpentine mesh sensor system.
• To address limitations of previous smart contact lenses by improving sensor modality, fabrication, mechanical stability, and biocompatibility.

Main Methods:

• Fabrication of ultrathin molybdenum disulfide (MoS2) transistors arranged in a serpentine mesh.
• Integration of photodetector, glucose sensor, and temperature sensor functionalities within the mesh system.
• Direct mounting of the sensor system onto contact lenses for tear fluid interaction and in vitro cytotoxicity testing.

Main Results:

• The serpentine mesh sensor system demonstrated high detection sensitivity for optical, glucose, and temperature sensing.
• The integrated sensors maintained mechanical robustness and did not impede blinking or vision.
• In vitro tests confirmed good biocompatibility of the smart contact lenses.

Conclusions:

• A novel, flexible fabrication approach enables multifunctional smart contact lenses with integrated MoS2 transistor sensors.
• The developed smart contact lenses offer a promising platform for continuous, non-invasive monitoring of physiological parameters like glucose levels.
• These smart contact lenses represent a significant step towards next-generation soft electronics for advanced healthcare and medical applications.