The invention relates to a contact release capsule comprising a particle, a chemical payload, and a polymer coating, wherein the particle is impregnated with the chemical payload, and the chemical payload is held inside the particle by the polymer coating until the contact release capsule contacts a surface and a shearing force removes the polymer coating allowing the chemical payload to release outside the particle. The contact release capsule is useful in chemical mechanical planarization slurries. Particularly, the contact release capsule may comprise a glycine impregnated silica nanoparticle coated with a polymer, wherein the contact release capsule is dispersed in an aqueous solution and used in the copper chemical mechanical planarization process. Use of the contact release capsule in a slurry for copper chemical mechanical planarization may significantly improve planarization efficiency, decrease unwanted etching and corrosion, and improve dispersion stability.