Determination of molybdenum and tungsten in biological materials

A spectrophotometric method for the quantitative determination of molybdenum and tungsten in the presence of each other in biological materials, has been developed. The method involves the selective formation and extraction of the complexes of the metals with 4-methyl-1,2-dimercaptobenzene under specified conditions of acidity and temperature. Possible interference by components found in biological materials, was examined and shown to be negligible.