▎ 摘　　要

NOVELTY - Composite membrane material, comprises high molecular polymer materials and modified polymers, where the high molecular polymer material includes at least one of copolymerized divalent ester polymer, acrylate and urethane, the molecular weight of the composite membrane material is 15000-30000, and the molecular weight distribution index D of the composite membrane material is 1.3-1.6. USE - The composite membrane material is useful in biosensor (claimed). ADVANTAGE - The composite membrane material: has non-toxic, non-irritating properties, good biocompatibility, and both good biocompatibility and good permeability selectivity; can improve the selective permeability of tissue fluid; allows the blood sugar, lactic acid, ketones, etc. to pass through the tissue fluid; and avoids the blockage of the composite membrane material when working for a long time and thus improving the sensitivity and working efficiency of the biosensor. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for biosensor, comprising a working electrode, at least one counter electrode, a reference electrode, a detection layer, where the detection layer contacts the working electrode, the detection layer includes the composite membrane material and an enzyme that transmits electrons to the working electrode and receives electrons from the working electrode.