Highly selective electrochemical detection of diphenylamine in apple samples using rod shaped CuCo2O4 derived from bimetallic organic frameworks

Trace level valuation of analytes is always needed to develop a feasible sensor. In summary, using copper-cobalt oxide (CuCo2O4), the diphenylamine (DPA) sensor has been constructed. A rod like structured Cu/Co metal?organic framework (MOFs) was obtained by one-step chemical synthesis. Then, CuCo2O4 was obtained by simple oxidation of Cu/Co-MOFs. The formation of particles on the rod was due to the decomposition of organic ligands and confirmed by physical characterizations like FE-SEM and XRD studies. A high surface with better conductivity has been supported by BET analysis. The obtained CuCo2O4 was further electrochemically characterized using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV) method. In CV, the optimum working potential was -0.3 to 1.0 V and the peaks obtained were at lower potential (0.544). Further, Obtained DPV results for CuCo2O4/GCE attains a lower LOD of 0.00267 ?M with a respectable linear range. Further, CuCo2O4/GCE showed excellent selectivity, good reproducibility, repeatability, and better stability. Also, the developed CuCo2O4/GCE electrode was additionally used to analyze the DPA in real-time fruit juice samples (apple fruit and apple juice).

Automated summary

The study describes the construction of a DPA sensor using CuCo2O4. Cu/Co MOFs were obtained through chemical synthesis and further oxidized to CuCo2O4, which has a high surface area and good conductivity. Characterization using various electrochemical methods showed lower detection limit and good stability of CuCo2O4, making it suitable for real-time analysis of DPA in fruit juice.