Application of modem analytical technology for studying the fate of metallodrugs after administration to the blood is of utmost importance for drug development Zn(II) compounds are under development as insulin-enhancing drugs with potential use in the treatment of diabetes. in comparison to the well-established vanadium compounds, especially the lower risk of adverse effects due to the essentiality of the element in biological processes is advantageous. Herein, CZE-ICP-MS studies on the interaction of Zn(II)-maltolato, -2-picolinato and -2,6-dipicolinato complexes with human serum proteins are discussed and modeling calculations were confirmed by experimental results. Studies with human serum reveal preference for HSA over other less abundant proteins and serum components.