Nanoengineered paper-based electrochemical sensor for an extended linear range in H2O2 determination

In this study, a disposable paper-based electrochemical sensor was developed for detecting hydrogen peroxide (H2O2) in disinfectant solutions. A screen-printed electrode comprising carbon working and auxiliary electrodes, along with an Ag/AgCl reference electrode, was fabricated on office paper. Subsequently, the working electrode surface was nanoengineered via a two-step procedure: first, gold nanoparticles (AuNPs) were electrodeposited onto the bare screen-printed paper electrode (SPE); second, the surface was further modified with carbon black (CB) and Prussian blue nanoparticles (PBNPs) nanocomposite. Scanning electron microscopy analysis and cyclic voltammetry were utilized to characterize the nanoengineered sensor. Under optimum experimental conditions, the sensitivity and detection limit of the sensor were found to be 7.4 μAmM−1 and 0.9 μM, respectively, with an extended linear range equal to 3 μM–10 mM. The practical applicability of the CB-PBNPs/AuNPs/SPE was evaluated using commercial disinfectant solutions, yielding satisfactory results. The presented system demonstrated the utility to customize the modification of the working electrode for offering rapid, accurate, low-cost, and practical analysis of H2O2.