Colorimetric Detection of Acid Phosphatase Using Nanoparticle CuNCs as Peroxidase Mimicking Activity

Abstract

ABSTRACT Acid phosphatase (ACP) serves as a critical biomarker for disease diagnosis, yet conventional detection methods face limitations in cost and complexity. Copper nanoclusters (CuNCs), leveraging Earth‐abundance, low expense, and noble metal‐like catalytic properties, offer an ideal nanozyme platform. This study harnesses the intrinsic peroxidase mimicking activity of CuNCs to construct a visual colorimetric sensor for ACP detection. CuNCs oxidize the substrate 3,3′,5,5′‐tetramethylbenzidine (TMB) to generate a blue chromogen (λmax = 654 nm). ACP introduction triggers reduction of this chromogen, diminishing both color intensity and absorbance. The optimized sensor achieves a linear detection range of 0–6 U/L with a detection limit of 0.027 U/L, demonstrating high sensitivity and specificity. This CuNCs‐based platform provides a rapid, low‐cost, and operationally simple approach for ACP quantification, highlighting significant potential for clinical diagnostics.