As stated earlier, glucose quantification relies on the enzymatic production of H2O2. While the permeability of H2O2 through the o-PD modification layers was anticipated , this phenomenon was experimentally confirmed in this study using CA method across different concentrations of H2O2. Fig. shows the CA curves for H2O2 electrooxidation and electro-reduction on the Au/Pt-B/o-PD/β-CD surface at increased concentrations of H2O2. The CA responses were obtained at ±0.25 V for 60 s measurements in the five different concentrations of H2O2 (0.1 to 1 mM), made up in 10 mM PB solutions (pH 7.4). An increase in the faradic current was observed for both the oxidation and reduction responses of H2O2 as the concentrations of H2O2 increased. The faradic current, which is linked to the electro-oxidation and electro-reduction of H2O2, quickly achieved a steady state and exhibited no signs of decrease during the testing phase. This suggests that the Au/Pt-B/o-PD/β-CD electrode surface has excellent stability in catalyzing the electro-oxidation and electroreduction of H2O2. The observations also affirm that H2O2 is capable of permeating through the modification layer, reaching the underlying platinum-modified surface, and undergoing electrochemical oxidation and reduction. The calibration plots of faradic current for both the oxidation and reduction responses versus H2O2 concentrations is presented in Fig. . The error bars represent the standard error between the mean current (n = 3), determined from the averaged values of last five seconds using 50 data points. Both the oxidation and reduction plots exhibit excellent linearity with a coefficient of deviation (COD) R 2 values of 0.999 and 0.995, respectively. This implies that a sensor's response to H2O2 follows a linear trend within the specified concentration range. The sensitivity for the oxidation and reduction responses of 34.82 nA.mM -1 and -38.47 nA.mM -1 were recorded from the slope of calibration plots. The calculated theoretical LODs were found to be 1.13 µM for the oxidative response and 0.45 µM for the reductive response. It is evident that the sensitivity and the LOD were superior in H2O2 electro-reduction compared to the H2O2 electro-oxidation, thus further experiments for glucose measurements were conducted by using the electrochemical reduction method. The CA responses of glucose measurements at -0.25 V for 60 s in 10 mM phosphate buffer solutions at pH 7.4 and pH 5.5 were depicted in Fig. and. An increase in faradic current was observed for both experimental cases as glucose concentrations increased (ranging from 0.05 to 2 mM), falling within the physiological salivary glucose range for calves (Contreras-Aguilar et al., 2021). Moreover, pH control was implemented to control the pH from 7.4 to 5.5, by applying a positive potential of 1.13 V at the protonator IDEs as illustrated in Fig. . These data correlated very well with the chemically controlled samples presented in Fig. confirming the suitability of the pH control method. The biosensor exhibited a steady-state response within 20 s of applying a potential in all cases. Calibration plots presented in Fig. show current versus glucose concentrations. A flat line (black line) was observed for the sensor fabricated without GOx, indicating that glucose responses originated solely from the GOx-modified chip. The buffered pH 5.5 calibration plot (green line) demonstrated a better sensitivity of -0.37 nA.mM⁻¹ compared to the pH 7.4 calibration plot -0.31 nA.mM⁻¹ (red line), confirming enhanced sensitivity at the lower pH level for GOx enzymes. However, the pH control calibration plot (purple line) exhibited even better sensitivity of -0.76 nA.mM⁻¹ and good linearity with R² = 0.980 compared to the other plots, with a theoretical LOD of 19.7 µM. This may be attributed to the production of molecular oxygen enhancing sensitivity as described above. The error bars depict the standard error calculated between the average current (with a sample size n = 3), determined from the final five seconds worth of data, which consists of 50 data points.