Doug Lloyd: The Separation, Identification, And Molecular Analysis Of Complex Mixtures Of Metalloproteins And Polypeptides By Tandemly linked Two-Dimensional HPLC-ICPMS. The utility of tandemly coupled two-dimensional HPLC-ICPMS for the separation and elemental quantification of mixtures of metalloproteins and polypeptides has been evaluated.  The technique has been applied to the separation of a mixture of Alkaline Phosphatase (AP), Metallothionein (Mt), Reduced Glutathione (GSH), and Oxidized Glutathione (GSSG).  Proteins were separated in the first dimension by size exclusion and similarly sized molecules were fractionated in the second dimension based on charge.   The success of the separation procedure was monitored by two diode array spectrometers, by elemental signatures, and by colorimetric arrays designed to test for enzymatic activity or substrate concentration.  The results showed that the system could distinguish all of the individual components, although baseline resolution between GSH and GSSG was never achieved.  Verification of the separation was obtained through the elemental profiles of Zn for AP and Zn, Cd, and Cu for Mt, the dephosphorylation of p-nitrophenyl phosphate by the enzymatic activity of AP, and the reduction of DTNB by a Glutathione reductase, NADPH recycling assay for GSSG and GSH.