Synthesis of Mesoporous CuO Hollow Sphere Nanozyme for Paper-Based Hydrogen Peroxide Sensor

Point-of-care monitoring of hydrogen peroxide is important due to its wide usage in biomedicine, the household and industry. Herein, a paper sensor is developed for sensitive, visual and selective detection of H2O2 using a mesoporous metal oxide hollow sphere as a nanozyme. The mesoporous CuO hollow sphere is synthesized by direct decomposition of copper-polyphenol colloidal spheres. The obtained mesoporous CuO hollow sphere shows a large specific surface area (58.77 m(2) /g), pore volume (0.56 cm(3) /g), accessible mesopores (5.8 nm), a hollow structure and a uniform diameter (similar to 100 nm). Furthermore, they are proven to show excellent peroxidaselike activities with K-m and V-max values of 120 mM and 1.396 x 10(-5) M.s(-1), respectively. Such mesoporous CuO hollow spheres are then loaded on the low-cost and disposable filter paper test strip. The obtained paper sensor can be effectively used for detection of H2O2 in the range of 2.4-150 mu M. This work provides a new kind of paper sensor fabricated from a mesoporous metal oxide hollow sphere nanozyme. These sensors could be potentially used in bioanalysis, food security and environmental protection.

Automated summary

A paper sensor has been developed for sensitive, visual and selective detection of H2O2 using mesoporous CuO hollow sphere as a nanozyme. The sensor can effectively detect H2O2 in the range of 2.4-150 μM.