The addition of metal salts to dendrimer for coordination to heteroatoms is well-documented. This interaction involves the coordinate covalent bond (Heteroatom--> to Metal).
However, addition of a reducing agent such as sodiumborohydride converts the metal ions to nanoparticles. How do these nanoparticles stay close to heteroatoms? What is the interaction between them? Why nanoparticles does not leach out immediately?