Nanozyme-based point-of-care testing: Revolutionizing environmental pollutant detection with high efficiency and low cost

Expanding human activities and unsustainable production patterns have resulted in the widespread release of pollutants into the environment, posing significant threats to both ecological environment and human health. To enable continuous environmental monitoring and timely pollution control, there is a critical need for low-cost, on-site, and rapid testing methods for detecting environmental pollutants. Point-of-care testing (POCT) has emerged as an attractive approach due to its portability, speed, user-friendliness, and cost-effectiveness compared to traditional laboratory detection methods. While natural enzymes have traditionally served as signaling molecules in POCT, they exhibit limitations such as poor stability and high production costs. In this context, nanozymes, which possess enzyme-mimicking capabilities coupled with high stability and low cost, have emerged as excellent substitutes for natural enzymes. The integration of nanozymes into POCT systems has resulted in enhanced economy, robustness, and improved application prospects. Recent studies have demonstrated the successful application of nanozyme-based POCT for detecting a wide range of environmental pollutants, including toxic ions, phenolic compounds, pesticide residues, antibiotic residues, and pathogenic bacteria. In this review, we provide a brief overview of the commonly used POCT devices for environmental pollutant detection. Moreover, the principle of nanozyme-based POCT is expounded. Furthermore, we summarize the progress of nanozyme-based POCT, highlighting strategies to enhance detection performance. Finally, we discuss existing challenges and propose future directions for nanozyme-based POCT in the field of environmental pollutant detection, with the aim of contributing valuable insights for the development of this promising field.