Cell biology and nanomedicine would strongly benefit from having access to information on the metal contents with single cell resolution, rather than at population scale. Metals are intrinsically present in cells to fulfill a wide variety of biochemical functions or are deliberately imported into cells, e.g., in the context of novel cell therapies, relying on the use of nanotechnology. However, very few analytical techniques are capable of quantifying metals at single-cell, or even sub-cellular, resolution. Novel technological breakthroughs in ICP-mass spectrometry have shown the potential of this technique for high throughput single-cell analysis. The main goal of this project is the development of analytical methodology to extend the application range of single-cell ICP-MS analysis and to move forward from proof-of-concept studies to the real-world. As the technique is still in its infancy, method development, optimization and validation are required to guarantee the quality of information that was virtually inaccessible until now. On the way to real-life applications, custom methods will be developed to address important questions in nanomedicine and to push the limits of single-cell metallobiology for obtaining both elemental and isotopic information from cells and subcellular structures. This unique approach will contribute to a better understanding of the role of metals in health and disease and to the development of better targeted cell-based therapies.