▎ 摘　　要

NOVELTY - Preparation of gold-magnetite doped palladium supported on zeolitic imidazolate framework-8 (Au-Fe3O4 at Pd-ZIF-8) based sandwich type immunosensor involves coating 6 mu L 1-3 mg/mL gold doped graphene oxide-thorium into glassy carbon electrode surface, polishing with aluminum oxide powder, drying at room temperature, rinsing using ultra-pure water and drying; dropping 6 mu L 8-12 g/mL tumor marker capture antibody Ab1 solution, incubating, rinsing with ultra-pure water and drying; and dropping 3 mu L 0.5-2.5 wt.% bovine serum albumin solution, rinsing with ultra-pure water and drying. USE - Method for preparing Au-Fe3O4 at Pd-ZIF-8 based sandwich type immunosensor (claimed). ADVANTAGE - The immunosensor has strong specificity, high sensitivity and low detection limit. DETAILED DESCRIPTION - Preparation of Au-Fe3O4 at Pd-ZIF-8 based sandwich type immunosensor comprises coating 6 mu L 1-3 mg/mL gold doped graphene oxide-thorium into glassy carbon electrode surface, polishing with aluminum oxide powder, drying at room temperature, rinsing using ultra-pure water and drying; dropping 6 mu L 8-12 g/mL tumor marker capture antibody Ab1 solution, incubating, rinsing with ultra-pure water and drying at 4 degrees C in refrigerator; dropping 3 mu L 0.5-2.5 wt.% bovine serum albumin solution, rinsing with ultra-pure water and drying at 4 degrees C in refrigerator; dropping 6 mu L 0.1 pg/mL to 50 ng/mL tumor marker antigen Ag solution, rinsing with ultra-pure water and drying at 4 degrees C in refrigerator; and dropping 6 mu L 1-5 mg/mL Au-Fe3O4 at Pd-ZIF-8-Ab2 capture antibody solution and drying at 4 degrees C in refrigerator.