Cu2(OH)3NO3 nanozyme sensor array for the discrimination of multiple sulfides in food.

ABSTRACT

In the food industry, sulfides are commonly used as preservatives and flavor regulators. However, long-term excessive intake of sulfides can lead to serious health problems. Therefore, developing efficient sulfide detection methods is particularly important. Here, we have effectively synthesized a novel bifunctional copper hydroxide nitrate (Cu2(OH)3NO3) nanozyme with outstanding peroxidase-like and laccase-like behaviors in basic deep eutectic solvents (DES). Because the various types of sulfides have diverse regulatory effects on the two catalytic behaviors of Cu2(OH)3NO3, a two channel nanozyme sensor array based on the peroxidase-like and laccase-like behaviors of Cu2(OH)3NO3 was constructed and successfully used for the identification of six kinds of sulfides (Na2S, Na2S2O3, Na2SO3, Na2SO4, NaHSO3, and Na2S2O8). Remarkably, the sensor array has achieved successful discrimination among six sulfides present in wine, egg, and milk samples. Finally, the sensor array has successfully distinguished and differentiated three actual samples (wine, egg, and milk). This study is of great significance in promoting the efficient construction of array units and improving the effective identification of sulfides in complex food samples.