We develop robust core-shell nanoparticles that serve as advanced imaging probes to study how cells interact with nanomaterials. These particles feature a protective shell surrounding a metallic core, creating stable platforms for tracking cellular processes. The metallic cores, such as gold, combined with fluorescent-embedded shells, enable us to visualize nanoparticle movement using multiple imaging techniques simultaneously. Through careful surface engineering, we investigate how these particles enter cells and distribute throughout biological systems and what ultimately happens to them. This research provides crucial insights for developing safer and more effective nanomaterials for biological applications.