Laser-inscribed contact lens sensors for the detection of analytes in the tear fluid


Tears exhibit compositional variations as a response to ocular and systemic metabolic conditions, and they can therefore be used for the assessment of physiological health. Here, microfluidic contact lenses were developed as wearable platforms for in situ tear pH, glucose, protein, and nitrite ions sensing. The microfluidic system was inscribed in commercial contact lenses by CO2 laser ablation. The microchannel consisted on a central ring with four branches, and biosensors were embedded within microcavities located at the branches ends. The device was tested with artificial tears and colorimetric readouts were performed using a smartphone-MATLAB algorithm based on the nearest neighbor model. Sensors responded within a time range of 15 s, and yielded sensitivities of 12.23 nm/pH unit, 1.4 nm/mmol L−1 of glucose, 0.49 nm/g L−1 of proteins, and 0.03 nm/μmol L−1 of nitrites. Contact lens sensing platforms may provide on-eye tears screening with applications in the monitoring of the ocular health both in clinics and at point-of-care settings.

Publication DOI:
Divisions: College of Health & Life Sciences > School of Optometry > Optometry
Funding Information: R.M. thanks James Procter (No7 Contact Lenses, UK) for supplying RGP contact lenses, and the School of Chemical Engineering at the University of Birmingham for funding.
Additional Information: © 2020, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
Uncontrolled Keywords: Biomarkers,Biosensors,Contact lenses,Point-of-care diagnostics,Tear fluid,Electronic, Optical and Magnetic Materials,Instrumentation,Condensed Matter Physics,Surfaces, Coatings and Films,Metals and Alloys,Electrical and Electronic Engineering,Materials Chemistry
Publication ISSN: 0925-4005
Last Modified: 16 Jul 2024 07:16
Date Deposited: 01 Jun 2020 08:34
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Related URLs: http://www.scop ... tnerID=8YFLogxK (Scopus URL)
https://www.sci ... 5281?via%3Dihub (Publisher URL)
PURE Output Type: Article
Published Date: 2020-08-15
Published Online Date: 2020-04-30
Accepted Date: 2020-04-22
Authors: Moreddu, Rosalia
Wolffsohn, James S. (ORCID Profile 0000-0003-4673-8927)
Vigolo, Daniele
Yetisen, Ali K.

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