In this paper we report on the synthesis of robust water-soluble gold nanoparticles, suitable for biological applications. We show that specifically functionalized nanoparticles such as nanospheres, nanorods and hollow gold particles can migrate either on the cellular membrane or be endocytosed. A theoretical model is employed to discuss the potential use of these particles as tools for laser treatment of endothelial cells. Our studies open up new avenues towards manipulation of cells using gold nanoparticles and laser treatment.