After the fabrication process of the microband IDEs, individual sensors (Fig. ) were ready for the modification process. Prior to use, sensors were subsequently cleaned by ultrasonication in acetone, IPA and DI water for 3-5 min each to remove the protective photoresist and to clean any dirt from the surface of the sample. A typical image of a single working electrode along with its cross-sectional view is shown in Fig. . The modification procedure, as illustrated in Fig. , closely followed the method outlined in the literature ( . Recognizing platinum's role in catalyzing water electrolysis, Pt was electrodeposited on protonator IDEs to facilitate the production of proton flux at lower overpotentials . A platinum-black deposition was carried out via chronoamperometric (CA) approach from a solution containing 15 mM chloroplatinic acid hexahydrate and 2.4 mM lead (II) acetate trihydrate, at -0.375 V against the on-chip platinum pseudo RE for 120 s. A layer of o-PD/β-CD/GOx was electrodeposited by applying a positive potential of 0.7 V using the on-chip Pt RE for 1200 s. The electro-polymerization process (Fig. ) was performed using a solution that contained a mixture of 5 mM Na2SO4, 10 mM o-PD, 15 mM β-CD, and 5 mg/mL of GOx, all in a 50 mM phosphate buffer (PB) solution (comprising sodium phosphate monobasic and sodium phosphate dibasic) with a pH of 7.4. After this modification step, WEs were rinsed with a 10 mM PB solution to remove any enzyme that was not attached to the microband electrodes. Subsequently, the chips were stored in 50 mM PB (pH 7.4) at 4 °C overnight to allow the biosensors achieve stability.