Coatings
Most nanomaterials, especially those synthesized in liquid media, need an additional chemical to keep particles suspended in liquid without contacting one another and aggregating. This additional chemical, usually a polymer or surfactant in nature, is known as a coating, stabilizer, or capping agent. Coatings may interfere with the properties, behavior, and toxicity of nanomaterials and for this reason, should be reported along with nanomaterial composition.