▎ 摘　　要

NOVELTY - The utility model claims a composite film modified electrode based on phenylneovaricaine A (PEA-A) detecting sensor, the sensor comprising a composite film modified electrode as working electrode, the composite film modified electrode comprises glassy carbon substrate, the glassy surface of the substrate modified with a GO-AB layer, said GO-AB layer is loaded with Fe3O4 @ SiO2 layer. the result shows, the electric catalytic oxidation-reduction feature of Fe3O4 @ SiO2/GO-AB/GCE exhibits good PEA-A. in 0.10mol/L of PBS buffer solution (pH=6.5), the concentration of the response peak current and PEA-A of the modified electrode has good linear relation, the linear range is 1.0 to 1000nmol/L, the detection limit is 0.12nmol/L (S/N= 3). the electrode has good repeatability, stability and anti-jamming capability. the electrode for measuring PEA-A in pig serum and urine sample and the recovery rate are respectively 96.0% ~ 110.0 % and 93.8% ~ 104.7 %, which indicates that the electrode in healthy cultivation biochemical detection fields with important application value.