Protein blotting method for detection of nickel-binding proteins

A technique is described for detection of nickel-binding proteins in tissue extracts by protein blotting and autoradiography. The proteins are separated by SDS-polyacrylamide gel electrophoresis and blotted onto a nitrocellulose membrane. The membrane is incubated with 63NiCl2 in a tris-HCl buffer that contains NaCl and CaCl2 to suppress non-specific Ni-binding. The membrane is washed to remove unbound 63Ni2+ and autoradiography is performed to visualize the 63Ni-binding proteins. The technique furnishes a sensitive means to detect 63Ni-binding proteins in tissue extracts, facilitating their isolation, characterization, and identification.