Both silver and gold have been employed for the metallic impregnation of amyloid. Either will selectively demonstrate the material, but have not been proven to be specific.
King's silver method is quite straightforward but requires free floating frozen sections. Staining involves simply treating formalin fixed, free floating sections with an ammoniacal silver solution until stained. No chemical reduction is used.
Lynch and Inwood's gold impregnation depends on the affinity of amyloid for iodine. Sections are sequentially treated with iodine then gold. Finally, the product is oxidised with hydrogen peroxide.
These methods are not popular. Partly this is due to the expense of silver and gold, but also due to the simplicity and convenience of other, dye staining, methods.
|Metallic Impregnation Methods|
|Lynch & Inwood's gold|
Last updated July 2012.