Metal ion complexes are playing an increasing role in the development of antimicrobials. We review here the antimicrobial properties of cobalt coordination complexes in oxidation state 3+. In addition to reviewing the cobalt complexes containing polydentate donor ligands, we also focus on the antimicrobial activity of the homoleptic [Co(NH₃)₆]³⁺ ion.

A comprehensive survey on the methods for the surface modification of plasmonic noble metal–metal oxide core–shell nanoparticles is presented. The review highlights various strategies for covalent attachment and electrostatic binding of molecules and molecular ions to core–shell nanoparticles with a focus on plasmonically active silver and gold nanoparticles encapsulated by SiO₂ and TiO₂ shells.