Colorimetric sensor arrays for antioxidant recognition based on Co3O4 dual-enzyme activities

A sensor array based on the double enzyme–like activity of Co 3 O 4 nanozymes was constructed to identify four different antioxidants. Due to the double enzyme–like activity of Co 3 O 4 , oxTMB appears blue with different degrees in the presence and absence of H 2 O 2 .