Metal‐based nanoparticle interactions with the nervous system: the challenge of brain entry and the risk of retention in the organism

This review of metal‐based nanoparticles focuses on factors influencing their distribution into the nervous system, evidence they enter brain parenchyma, and nervous system responses. Gold is emphasized as a model metal‐based nanoparticle and for risk assessment in the companion review. The anatomy and physiology of the nervous system, basics of colloid chemistry, and environmental factors that influence what cells see are reviewed to provide...