Prussian blue-supported platinum nanoparticles as pH-Universal catalase mimics: enabling robust chemiluminescent immunoassay for VEGF in clinical diagnostics

The synthesized PB@Pt exhibited high catalase (CAT)-like activity across a broad pH range, including alkaline media. Remarkably, in alkaline conditions, PB@Pt catalyzed the luminol-H₂O₂ reaction, producing CL signals significantly stronger than those achieved with natural HRP. Leveraging this enhanced performance, the established PB@Pt-based CL immunoassay enabled a wide linear detection range, ultra-low detection limits, high specificity, and excellent stability for VEGF quantification. This work introduces a novel strategy for designing CAT-mimicking nanozyme probes, thereby broadening their utility in CL immunoassays and advancing the clinical translation of nanozyme-based diagnostics for applications such as biomarker screening and point-of-care testing (POCT).