What Tears Tell Us About Neurological Health

An experimental graphene-based device could support future noninvasive neurological biomarker testing from tear samples

July 16, 2026
2 min

The Pathologist

Objective:

To explore the development of a low-cost electrochemical sensor for measuring dopamine in tears as a noninvasive method for monitoring neurological biomarkers.

Approach:

Sensor Development: Researchers created a sensor using laser-induced graphene modified with nickel nitrate and urea to enhance dopamine detection in tear fluid.
Testing Conditions: The sensor was evaluated in buffered laboratory solutions, synthetic tear fluid, and recovery experiments to mimic real-world conditions.

Key Findings:

The sensor demonstrated improved electron transfer and detection sites due to modifications, resulting in stronger and more selective responses.
It maintained stable function for at least one week post-fabrication and showed reliable responses across clinically relevant dopamine concentrations.
Recovery values approached 100 percent, indicating minimal interference from common tear components.

Interpretation:

Further validation in patient samples is required.

Limitations:

The sensor has not yet been validated in patient samples.
Further studies are needed to confirm correlation with neurological disease status or treatment response.