Porous microneedle-based electrochemical aptamer biosensor for collection and quantitative analysis of dry eye disease biomarkers

Abstract

Dry eye disease (DED) is a prevalent ocular disorder driven by tear film instability and inflammation. The quantitative measurement of molecular biomarkers in tears can provide a reliable, and accurate diagnosis and management of DED. This article introduces a porous microneedle-assisted electrochemical aptamer biosensor for the collection and quantitative analysis of DED-associated biomarkers in tear. The porous microneedle component collects tear while the electrochemical aptamer sensor detects interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), or matrix metalloproteinase-9 (MMP-9) with the detection limit of 4.46 pg/mL, 1.56 pg/mL, and 4.97 ng/mL, respectively. Clinically, DED is associated with 13 pg/mL of IFN-γ, 4 pg/mL of TNF-α, and MMP-9 concentrations of more than 40 ng/mL in tears, which are above the detection limits of our sensors. By taking MMP-9 as a model biomarker, we demonstrate a complete collection-to-detection workflow using this microneedle-aptamer biosensing device, which would facilitate the realization of point-of-care monitoring of DED.