Wearable Contact Lens Biosensors for Continuous Glucose Monitoring Using Smartphones

Research output: Contribution to journalArticle

Authors

Colleges, School and Institutes

External organisations

  • Department of Experimental Physics, Nuclear Research Center , Egyptian Atomic Energy Authority , Cairo , Egypt.
  • Optoelectronics Research Lab, Department of Physics , COMSATS University , Islamabad 45550 , Pakistan.

Abstract

Low-cost, robust, and reusable continuous glucose monitoring systems that can provide quantitative measurements at point-of-care settings is an unmet medical need. Optical glucose sensors require complex and time-consuming fabrication processes, and their readouts are not practical for quantitative analyses. Here, a wearable contact lens optical sensor was created for the continuous quantification of glucose at physiological conditions, simplifying the fabrication process and facilitating smartphone readouts. A photonic microstructure having a periodicity of 1.6 μm was printed on a glucose-selective hydrogel film functionalized with phenylboronic acid. Upon binding with glucose, the microstructure volume swelled, which modulated the periodicity constant. The resulting change in the Bragg diffraction modulated the space between zero- and first-order spots. A correlation was established between the periodicity constant and glucose concentration within 0-50 mM. The sensitivity of the sensor was 12 nm mM-1, and the saturation response time was less than 30 min. The sensor was integrated with commercial contact lenses and utilized for continuous glucose monitoring using smartphone camera readouts. The reflected power of the first-order diffraction was measured via a smartphone application and correlated to the glucose concentrations. A short response time of 3 s and a saturation time of 4 min was achieved in the continuous monitoring mode. Glucose-sensitive photonic microstructures may have applications in point-of-care continuous monitoring devices and diagnostics at home settings.

Details

Original languageEnglish
Pages (from-to)5452-5462
Number of pages11
JournalACS Nano
Volume12
Issue number6
Early online date11 May 2018
Publication statusPublished - 26 Jun 2018

Keywords

  • contact lenses, glucose sensors, phenylboronic acid, photonic nanostructures, smartphone diagnostics, wearable sensors