The separation of protein-bound iodine and nonprotein iodine by serum coagulation.

HE SEPARATION of protein from nonprotein material, a usual procedure in the analysis of biological specimens, has been effected in a ilumber of ways. Marymont and London (1) have reported a new coagulalation technic which is perhaps advantageous in certain instances, as well as several applications of the technic (2-6). it is well known that the precipitation of proteins by any of the conventional protein precipitants, yields a nonprotein fraction containing excess protein precipitant in solution. If one is interested in studying various naturally occurring constituents in the aqueous nonprotein fraction, the removal of the excess protein precipitant can be difficult and in some cases almost impossible. However, removal may be accomplished by simply coagulating the proteins and extracting the coagulum with water. We have investigated the washed coagulum and also the water-soluble fraction for iodine.