Evaluating Analytical Performance of Commercial Screen-Printed Electrodes for Point-of-Care Uric Acid Sensing: A Comparative Study

Uric acid (UA), a key purine metabolite associated with metabolic, cardiovascular, and renal disorders, has been extensively investigated using electrochemical sensors. Increasing efforts now focus on translating these technologies into commercial point-of-care (POC) platforms for rapid, decentralized detection. Commercial screen-printed electrodes (SPEs) are widely employed as substrates for such platforms, typically after surface modification with nanomaterials or recognition elements; however, their inherent, unmodified analytical capabilities remain largely uncharacterized. This gap is significant, as the baseline performance of the underlying electrode ultimately constrains or enables the benefits of any subsequent modification. Here, we systematically compare two commercially available SPEs, DRP-110 and DRP-150, for UA detection using differential pulse voltammetry under standardized conditions. Both electrodes exhibited two distinct UA oxidation peaks. The first peak gave linear calibration over 0.02–0.5 µM (R2 = 0.9863 DRP-110, 0.9928 DRP-150), with validated LOD/LOQ of 0.076/0.230 µM (DRP-110) and 0.055/0.166 µM (DRP-150); the second peak extended the linear working range to 1–1000 µM (DRP-110, R2 = 0.9833) and 1–2000 µM (DRP-150, R2 = 0.9928), with LOD/LOQ of 3.37/10.20 µM and 2.23/6.77 µM, respectively, derived from its low-concentration segment. DRP-150 demonstrated superior sensitivity at both peaks. However, both electrodes showed low selectivity toward ascorbic acid. Spike recovery testing in modified artificial urine gave recoveries of 68.0–98.49%, supporting preliminary feasibility in a defined urine-like matrix.