Lab‐on‐a‐Contact Lens Platforms Fabricated by Multi‐Axis Femtosecond Laser Ablation

Abstract

Contact lens sensing platforms have drawn interest in the last decade for the possibility of providing a sterile, fully integrated ocular screening technology. However, designing scalable and rapid contact lens processing methods while keeping a high resolution is still an unsolved challenge. In this article, femtosecond laser writing is employed as a rapid and precise procedure to engrave microfluidic networks into commercial contact lenses. Functional microfluidic components such as flow valves, resistors, multi‐inlet geometries, and splitters are produced using a bespoke seven‐axis femtosecond laser system, yielding a resolution of 80 µm. The ablation process and the tear flow within microfluidic structures is evaluated both experimentally and computationally using finite element modeling. Flow velocity drops of the 8.3%, 20.8%, and 29% were observed in valves with enlargements of the 100%, 200%, and 300%, respectively. Resistors yielded flow rate drops of 20.8%, 33%, and 50% in the small, medium, and large configurations, respectively. Two applications were introduced, namely a tear volume sensor and a tear uric acid sensor (sensitivity 16 mg L−1), which are both painless alternatives to current methods and provide reduced contamination risks of tear samples.

Biomechanical analysis of ocular diseases and its in vitro study methods

“…Colorimetric readout based on the nearest neighbor model is carried out by MatLab algorithm of smart phone. They then further developed a laboratory platform for contact lenses using multiaxial femtosecond laser ablation [ 89 ] to quickly and accurately etch microfluidic networks on the surface of contact lenses. Production of functional microfluidics components such as flow valves, resistors, multi-entry geometry, and dispensers were realized with custom seven-axis femtosecond laser systems.…”

Lab‐on‐a‐Contact Lens: Recent Advances and Future Opportunities in Diagnostics and Therapeutics

“…[8] Furthermore, the tear fluid provides an on-demand supply for continuous and real-time health monitoring since it contains a wide variety of physiological indices such as proteins, glucose, and pH. [9,10] With the development of wearable bioelectronics, numerous efforts have been made to develop smart contact lenses (SCLs) that sense through the tear fluid.…”

Femtosecond Laser Ablation Assisted NFC Antenna Fabrication for Smart Contact Lenses

“…More et al presented a microfluidic-based SCL for colorimetric quantification of uric acid in tears. [41] An integrated contact lens sensor was demonstrated by utilizing multifunctional ultrathin MoS 2 transistors for multiplexed detection of glucose, temperature, and optical information. [34] Kim et al represented an SCL for multifunctional detection of glucose and intraocular pressure.…”