Metallothionein-determination in biological materials: interlaboratory comparison of 5 current methods.

Abstract

Five current methods of metallothionein (MT)-estimation in biological materials (Hg/TCA-, Cd/heme-, SH-assay, G 75-method and RIA) were compared. Uniform calibration was ensured by measuring the nitrogen-content of the standard-apoprotein after "Kjeldahl-digestion". Known amounts of rabbit standard Cd-MT I were recovered from identical rat S9-samples. In an overall rating, RIA and Cd/heme-assay performed best, whereas the other methods either underestimated (SH-, G 75) or overestimated (Hg/TCA) the 100%-expectation.