An improved method for analysis of distribution of metalloproteins in human liver cytosol by synchrotron radiation X-ray fluorescence

A method for the analysis of trace elements in protein bands with synchrotron radiation X-ray fluorescence (SRXFR) after electrophoresis separation was improved. Through a step of drying the gel before determination, the continues background mainly originated from the Compton scattering of X-ray upon the dry gel matrix was reduced to about one tenth of that upon the wet gel. Trace elements lighter than zinc in protein bands can be determined simultaneously. The method could be used for speciation of trace elements in biological sample.. Applying the improved procedure to investigate the distribution of metalloproteins in human liver cytosol,. six Zn-containing proteins with molecular weights(MWs) of 17.5, 20.5, 27, 35, 55, and 6 3 kdalton respectively, and four Fe-containing proteins with MWs of 20, 23, 43, and 83.5 kdalton respectively can be detected.. The 63 kdalton Zn-containing protein is the dominant form of zinc in the sample.