Speciation of Intracellular Zn, Fe and Cu within both iPS Cells and Differentiated Cells Using HPLC Coupled to ICP-MS

Zinc, iron and copper are essential mineral nutrients for the human body to function. It is also known that there are biological processes which relate to metals in the body including cells. Therefore, understanding about intracellular metals is important for the regeneration medicine. Intracellular metals were thought to be able to be divided into two forms by function: i) protein binding metals and ii) labile metals. However, it is difficult to quantify the concentration in both intracellular metal forms. In this study, the analytical method including the pre-treatment and HPLC coupled to ICP-MS (HPLC-ICP-MS) techniques was developed. Our method is able to fractionate two forms of intracellular metals and quantify each concentration, simultaneously. Finally, the presented method was applied to analysis of several cell states. As a result, dynamic changes of intracellular metal concentration were demonstrated during cell differentiation from iPS cells to pancreatic β cells.