Colorimetric sensor arrays for antioxidant recognition based on Co<sub>3</sub>O<sub>4</sub> dual-enzyme activities
Pingping Hao, Zhenchao Liu, Zhiwei Wang, Min Xie, Qingyun Liu
Abstract
. Interestingly, after the addition of antioxidants, the sensor array showed cross-reactions, and different changes in color and absorbance were observed, as TMB and antioxidants competed for binding. Different colorimetric responses were obtained on the sensor array and identified by linear discriminant analysis (LDA). The LDA result indicated that the sensor array can be used to distinguish 4 antioxidants, namely, dopamine (DA), glutathione (GSH), ascorbic acid (AA), and cysteine (Cys) at seven different concentrations, namely, 10, 20, 30, 50, 100, 200, and 250 nM. Different concentrations of antioxidants and proportions of mixed antioxidants were determined. This demonstrates the potential application of sensor arrays in diagnosis and food monitoring.