R. Moreddu, N. Mahmoodi, P. Kassanos, D. Vigolo, P.M. Mendes, A.K. Yetisen, Stretchable Nanostructures as Optomechanical Strain Sensors for Ophthalmic Applications, ACS Appl. Polym. Mater. (2021), DOI: 10.1021/acsapm.1c00703

Abstract

The intraocular pressure (IOP) is a physiological parameter that plays a crucial role in preventing, diagnosing, and treating ocular diseases. For example, lowering the IOP is the primary focus of glaucoma management. However, IOP is a widely varying parameter, and one-off measurements are prompt to errors. Developing portable solutions for continuous monitoring the IOP is a critical goal in ophthalmology. Here, stretchable nanostructures were developed as strain-tunable diffraction gratings and integrated into a contact lens. They exhibited a limit of detection (LOD) <2 mmHg and a linear response in the range of interest (15–35 mmHg). Nanopatterns were characterized under monochromatic laser sources and further integrated into a soft contact lens. A smartphone readout method based on preferentially reflected colors was proposed to pave the way toward smartphone-based ocular health monitoring.