Zr(IV)-based metal-organic framework nanocomposites with enhanced peroxidase-like activity as a colorimetric sensing platform for sensitive detection of hydrogen peroxide and phenol

Recently, metal-organic frameworks (MOFs) have great potential as an emerging peroxide-mimicking enzyme, and the improvement of its enzyme-like activity is desired. There are few studies on improving the peroxidase-like activity of MOFs by using the strategy of size reduction. Moreover, it is challenging to enhance the activity of Zr-based MOFs with peroxidase-mimicking activity by size reduction strategy. In this work, the synthesis of Zr-based MOFs capped with polyvinylpyrrolidone (Zr-MOF-PVP) was firstly reported to reduce crystal size of peroxidase-mimicking enzyme for enhanced catalytic activity. Using the 3,3',5,5'-Tetramethylbenzidine (TMB) as substrate, the synthesized Zr-MOF-PVP nanocomposites with nanosize (about 45 nm) possessed obviously enhanced peroxidase-like activity compared with the pristine Zr-MOF. Based on the above, the Zr-MOF-PVP was also successfully applied in constructing colorimetric detection. By using hydrogen peroxide (H2O2) and phenol as the model analytes, the satisfactory detection performance was obtained, indicating that the proposed method had an attractive application prospect in the field of peroxidase-related detection. Besides, this work also pro-vided a new perspective for improving the catalytic activity of nanozymes.

Automated summary

Recent studies have shown that improving the peroxidase-like activity of MOFs can be achieved through a size reduction strategy, and Zr-based MOFs have been successfully synthesized with a reduced crystal size to enhance catalytic activity. The synthesized Zr-MOF-PVP nanocomposites showed significantly enhanced peroxidase-like activity and were successfully applied in colorimetric detection and model analyte detection using H2O2 and phenol. This work provides a new perspective for improving the catalytic activity of nanozymes and has promising applications in peroxidase-related detection.