Smart Eye Patch Tracks Eye Health via Fluorescence

A research team led by Professor Jiang Changlong from the Institute of Solid State Physics at the Hefei Institutes of Physical Science, Chinese Academy of Sciences, has developed a wearable eye patch fluorescence sensor designed for noninvasive monitoring of lysozyme levels in human tears.

Published in the journal Analytical Chemistry, the study introduces a new method that combines multi-emission metal-organic framework hydrogel (Eu-Dy MOF gel) with smartphone-based color recognition to enable real-time, low-cost, and user-friendly eye health tracking.

Lysozyme: A Key Biomarker for Ocular Health

Lysozyme, often referred to as “the body’s own antibiotic,” plays a critical role in the eye’s immune defense system, protecting against bacterial infection. It also serves as an important biomarker for a range of ocular diseases. However, conventional lysozyme detection methods are often invasive or require specialized laboratory equipment.

Fluorescent Visualization Through a Smart Eye Patch

In this study, the team developed a noninvasive fluorescent detection system using a functionalized Eu-Dy MOF gel, which acts as a sensing unit within the wearable eye patch. The patch is applied to the skin beneath the eye, where it collects tear fluid secreted naturally.

The detection mechanism involves:

• A fluorescent signal emitted by the sensing area under ultraviolet (UV) light

• Image capture using the camera function of a smartphone

• Color analysis through smartphone-based software

This system enables simple, user-operated monitoring without the need for clinical intervention.

The Role of MOF Materials in High-Sensitivity Detection

The research highlights the use of MOF materials for their strong “antenna effect.” In this optical process, organic ligands within the MOF absorb light and transfer the energy to lanthanide ions such as Eu³⁺ and Dy³⁺, which then emit visible fluorescence.

In the presence of lysozyme, these MOF-based sensors undergo fluorescence quenching via static quenching and local electron transfer, which alters the color intensity captured by the smartphone.

High Sensitivity and Real-Time Monitoring Potential

The system demonstrated a detection limit as low as 1.5 nanomolar, indicating strong sensitivity and the potential for real-time, noninvasive biomarker monitoring.

“Our finding holds great potential for noninvasive detection of lysozyme in tears, promoting the widespread application of functionalized MOF fluorescent sensors in personal health monitoring, disease early warning, diagnosis, and treatment fields,” said Prof. Jiang.

Outlook

This innovation expands the application of fluorescent eye patch technology, offering a noninvasive, wearable, and smartphone-compatible solution for monitoring biomarkers related to eye health. The approach may pave the way for broader use in personal health diagnostics and early disease detection in ophthalmology.

Reference:

Lei Pan et al, Rare Earth Ion-Induced Functionalized Fluorescent MOF Hydrogel Patches for Monitoring Lysozyme in Tears, Analytical Chemistry (2025). DOI: 10.1021/acs.analchem.5c00346