The Method And Characteristic Of Receptor-binding Of ～(99m)Tc-EGF In-Vitro

Objective: To evaluate the method and characteristic of receptor-bindingof the potential breast cancer receptor imaging agent99mTc-EGF in vitro.Methods: EGF was direct labeled with 99mTc.According to a standard ofmaximum-binding rate, labeled EGF concentration, cell membraneconcentration, temperature, incubation time were changed individually.The method of 99mTc-EGF receptor-binding assay in vitro was set up.Based on the optimum method of receptor-binding, saturated andcompetitive inhibit study were accomplished.Results: The radiolabeling efficiency of 99mTc-EGF was 78.54％,thespecific activity was 2.77×1012Bq/g, and stability of 99mTc-EGF was wellso it could meet experimental and clinical needs. Radioreceptor bindingassay in vitro showed maximum-binding rate 39.30%.Saturated andcompetitive inhibit study showed that 99mTc-EGF had significantsaturated and competitive inhibit features, KD=4.425nmol,Bmax=3.788nmol .Conclusion: 99mTc-EGF remains the receptor-binding activity after theradiolabeling of 99mTc.It is a potential radiopharmaceutical agent for 3重庆医科大学硕士学位论文radioreceptor imaging of breast cancer.