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Here, we report on a novel nonenzymatic amperometric glucose sensor based on three-dimensional PtPb networks directly grown on Ti substrates using a reproducible one-step hydrothermal method. The surface morphology and bimetallic composition of the synthesized nanoporous PtPb materials were characterized using scanning electron microscopy and energy-dispersive X-ray spectrometry, respectively. Voltammetry and amperometric methods were used to evaluate the electrocatalytic activities of the synthesized electrodes toward nonenzymatic glucose oxidation in neutral media in the absence and in the presence of chloride ions. The synthesized nanoporous PtPb electrodes have strong and sensitive current responses to glucose. Their amperometric sensitivities increase in the order of Pt-Pb (0%) < Pt-Pb (30%) < Pt-Pb (70%) < Pt-Pb (50%). These nanoporous PtPb electrodes are also highly resistant toward poisoning by chloride ions and capable of sensing glucose amperometrically at a very low potential, -80 mV (Ag/AgCl), where the interference from the oxidation of common interfering species such as ascorbic acid, acetamidophenol, and uric acid is effectively avoided.

Biocatalytic transformations are exemplified by the electrical contacting of glucose oxidase (GOx) linked to the DNA scaffold with the electrode. Exchanging the positions of a nucleic acid-functionalized microperoxidase-11 (MP-11) and GOx on the DNA scaffold has eliminated the MP-11-electrocatalyzed reduction of [H.sub.2][O.sub.2].

The logic network composed of three enzymes operating in concert as four concatenated logic gates is designed to process four different chemical input signals. The coupling between signal-processing enzyme logic networks and electronic transducers might allow future electronic devices to respond to immediate physiological changes and have provided autonomous signaling/actuation depending on the concentration patterns of the physiological markers.