Influence of mineralizer in the preparation of Bi₂CuO₄ sensor for the electrochemical evaluation of chlorogenic acid in various real-time samples

Bismuth copper oxide (Bi₂CuO₄) has been prepared with varied morphologies and explored as an electrode modifier for chlorogenic acid (CGA) electrochemical sensors. The mineralizer agents such as NaOH, KOH, and NH₄OH served as a chemical agent and pH stabilizer in attaining variations in the morphology. The variation in the morphology attributes to the effect of viscosity of the corresponding mineralizer. The attained variation between the prepared Bi₂CuO₄ was revealed by different physicochemical characterization and electrochemical techniques. Bi₂CuO₄–KOH modified glassy carbon electrode (GCE) exemplifies an excellent redox performance, due to the higher ionic mobility and conductivity of KOH. The Bi₂CuO₄–KOH modified GCE was implemented towards the electrochemical sensing of CGA with the aid of differential pulse voltammetry (DPV). Further, it demonstrates exquisite electroanalytical performance including a wide linear range (0.05–556 μM) and nanomolar level detection (4.8 nM) with appraisable sensitivity of 0.22 μA/μM cm⁻² for oxidation. In addition, the proposed sensor exemplifies higher selectivity with excellent repeatability, reproducibility, and stability. Moreover, the practical feasibility analysis with various real samples displays excellent recovery results for the electrochemical sensing of CGA.