Abstract
Gout is a painful inflammatory arthritis associated with elevated uric acid (UA) levels in blood. Current monitoring methods rely on invasive blood testing and laboratory-based analysis, limiting frequent assessment. Here, we present LollyLab, a noninvasive lollipop-shaped electrochemical platform for salivary UA quantification, encouraging preventative lifestyle changes to reduce gout flare-ups and chronic joint deterioration. The device integrates sample collection, microfluidic transport, and sensing into a handheld format for point-of-care use. LollyLab employs Nafion-modified laser-induced graphene (LIG) electrodes and a phosphate-buffered saline preloaded glass fiber (PBS–GF) layer to enhance electrochemical performance in saliva. UA was quantified using square wave voltammetry (SWV) over a physiologically relevant range of 100–500
μ
M. The platform achieved a sensitivity of 0.015
μ
A
μ
M
−
1
in real saliva (
R
2
=
0.999
), a limit of detection of 12
μ
M, and a limit of quantification of 40
μ
M. Recovery studies demonstrated accuracies of 88.3%–102.6%. Human participant testing demonstrated close agreement with a commercial enzymatic assay, with relative errors below 15% across all subjects and strong user acceptance. Requiring only 90
μ
l of saliva and approximately 90 s for analysis, LollyLab provides a low-cost and user-friendly platform for salivary UA monitoring with potential applicability to additional salivary biomarkers.