Gold Silicon Oxide Core-Shell Nanoparticles probes allow for the study and visualization of cellular and molecular processes in vitro and in vivo; a critical tool for both basic science researchers and clinicians. The used in conjunction with biomedical imaging devices, they can provide bright, enhanced signals with significant differentiation from native tissue background. In certain applications, such as identifying sentinel lymph nodes, stable nanoparticles with passive coatings are sufficient.