Robust Pt/C nanozyme for total antioxidant capacity assay in daily foods

A robust oxidase (OXD)-like Pt/C nanozyme is proposed for the estimation of total antioxidant capacity (TAC) in foods. Vulcan XC-72 carbon material serves as both the support and stabilizer of the nanozyme, synthesized using a one-pot solvothermal method. A Pt/C nanozyme-based ascorbic acid (AA) quantitative colorimetric sensing platform was developed. The experimental results showed that the detection range for AA was 3-50 μM, with a detection limit of 0.93 μM, which is comparable with that of related studies. The proposed AA colorimetric could resist the interference from some metal ions, small bioactive molecules, and antioxidants, indicating its superior selectivity. The estimation of TAC in daily foods including commercial beverages and fruit juices was further explored, with results highly consistent with those obtained using the commercial kit detection method. Notably, the preparation process for Pt/C nanozyme was simple and well-suited for large-scale production, and it exhibited superior catalytic activity even after prolonged storage, indicating its substantial potential for real-time TAC detection. This work not only provided a robust strategy for synthesizing highly efficient nanozymes but also developed a convenient method for TAC detection to help individuals make informed dietary choices.