Presence of nickel in alpha-2 macroglobulin isolated from human serum by high performance liquid chromatography.

A two-step procedure was devised for purification of alpha 2-macroglobulin (alpha 2 M) from human serum by high performance liquid chromatography (HPLC) on "Superose 6" gel-filtration medium and "Mono-Q" ion-exchange medium. The isolated protein reacts with specific alpha 2 M-anti-serum upon immunoelectrophoresis, migrates as single protein band on SDS-acrylamide gel electrophoresis, and yields an approximate molecular weight of 7 x 10(5) Mr upon HPLC size-exclusion chromatography. Presence of nickel in the purified serum alpha 2 M was demonstrated by Zeeman electrothermal atomic absorption spectrophotometry, consistent with findings decades ago by less refined and sensitive techniques.