▎ 摘　　要

NOVELTY - Enzyme electrode comprises a working electrode, where the working electrode is a substrate electrode surface is fixed with xylose dehydrogenase and coenzyme NAD+ and further comprises a counter electrode, and optionally comprises or does not include a reference electrode. USE - Enzyme electrode used as electrochemical biosensor for detecting content of xylose (all claimed). ADVANTAGE - The electrode detects oxidation current of NADH by the electrochemical work station to realize detection of xylose. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for following: (1) a method for preparing enzyme electrode, which involves contacting the xylose dehydrogenase and NAD+-PEG complex with a carbon material with metal nanoparticles to make them co-immobilized on the surface of the carbon material to obtain an enzyme complex, and then modify the enzyme complex on the surface of the base electrode, preparing carbon material with metal nanoparticles, preparing NAD+-PEG complex, co-immobilization of xylose dehydrogenase and NAD+-PEG complex on the carbon with metal nanoparticles material to obtain an enzyme complex, and modifying the enzyme complex on the surface of the base electrode to obtain a working electrode; and (2) combining the working electrode, the counter electrode, and an optional reference electrode; (3) a method for detecting concentration of xylose, which involves dropping the xylose sample to be tested into the working area of the electrochemical biosensor, applying voltage, detecting the oxidation current of NADH, measuring oxidation current by timing current method or cyclic voltammetry, where voltage of the electrochemical detection for xylose is preferably 0-1 volt; and (4) a device for detecting content of xylose, which comprises electrochemical biosensor, a control component, a detection component, an operation component and an output component, where control component controls the voltage application of the biosensor, detecting component detects by the voltage applied to obtain electrochemical biosensor based on the detected sample in the substrate of the electronic to the electrode of the movement of the electrode generated by the charge transfer control current, calculating the concentration of the substrate by the current value by the calculation component, and output component outputs the calculated substrate concentration.