The synthesis and biodistribution of β-amyloid plaques imaging agent [131I]-2- (4′-dimethylaminophenyl)- 6-iodoimidazo[1,2-α] pyridine ([131I]IMPY) were reported. The chemical structure of the labeling precursor 2-(4′-dimethylaminophenyl)-6-(tributylstannyl)imidazo[1,2-α] pyridine and all its intermediates were verified by IR,HNMR and MS. The radioiodinated compound was prepared using iododestannylation reaction by hydrogen per-oxide. Final radiochemical purity was above 95% determined by TLC. The in vivo biodistribution of [131I]IMPY in normal mice showed excellent brain uptake and washout, indicating this thioflavin-T based small molecular probe has potential for in vivo imaging amyloid deposits. The synthesis and biodistribution of β-amyloid plaques imaging agent [131I] -2- (4’-dimethylaminophenyl) -6-iodoimidazo [1,2-α] pyridine The radioiodinated compound was prepared using iododestannylation reaction by hydrogen per-oxide (IR). The precursor 2- (4’-dimethylaminophenyl) -6- (tributylstannyl) imidazo [1,2-alpha] pyridine and all its intermediates were verified by IR, The final radiochemical purity was above 95% determined by TLC. The in vivo biodistribution of [131I] IMPY in normal mice showed excellent brain uptake and washout, indicating this thioflavin-T based small molecular probe has potential for in vivo imaging amyloid deposits.