Microengineered poly(HEMA) hydrogels for wearable contact lens biosensing
Yihang Chen1, Shiming Zhang2, Qingyu Cui3
1Center for Minimally Invasive Therapeutics (C-MIT), University of California-Los Angeles, Los Angeles, CA 90095, USA and California NanoSystems Institute, University of California-Los Angeles, Los Angeles, CA 90095, USA and Department of Materials Science and Engineering, University of California-Los Angeles, Los Angeles, CA 90095, USA.
Lab on a Chip
|October 13, 2020
Summary
Researchers created microchannels in hydrogel contact lenses using 3D printing. This innovation enables smart contact lenses with potential for tear flow and wearable biosensing applications.
Area of Science:
- Biomaterials Engineering
- Hydrogel Science
- Microfluidics
Background:
- Microchannels are crucial for smart contact lens functionality.
- Conventional microfabrication methods are incompatible with sensitive hydrogel materials used in commercial contact lenses.
Purpose of the Study:
- To develop a method for fabricating microchannels in poly(2-hydroxyethyl methacrylate) (poly(HEMA)) hydrogels.
- To investigate capillary flow behavior within these microchannels under varying hydration levels.
- To demonstrate the potential for integrated sensing capabilities in microchannel-containing hydrogels.
Main Methods:
- Utilized a three-dimensional (3D) printed mold for microchannel fabrication in poly(HEMA) hydrogels.
- Examined capillary flow dynamics across different hydrogel hydration states.
- Tested colorimetric pH and electrochemical sodium ion (Na+) sensing functionalities.
Main Results:
- Successfully fabricated microchannels within poly(HEMA) hydrogels suitable for contact lenses.
- Identified distinct capillary flow regimes influenced by the hydrogel's hydration level.
- Demonstrated that peristaltic pressure, mimicking eye blinking, can restore flow in dehydrated channels.
- Validated colorimetric pH and electrochemical Na+ sensing within the fabricated microchannels.
Conclusions:
- Microengineered poly(HEMA) hydrogels offer a viable platform for advanced contact lens development.
- The ability to control fluid flow and integrate sensing opens avenues for novel eye-care and wearable biosensing devices.
- This fabrication technique overcomes limitations of traditional methods for creating functional microchannels in commercial hydrogel contact lenses.
