The Electrospray Aerosol Generator (EAG) produces high concentrations of monodisperse, submicrometer particles from 2 to 100 nm (initial droplet diameter of 150 nm, nominal). The Electrospray pushes a charged liquid solution or suspension through a capillary tube and exerts an electrical field on the liquid at the capillary tip. The electrical field pulls the liquid from the capillary, forming individual droplets. Air and CO2 mixed with the droplets evaporate the liquid and the remaining particles are neutralized by an ionizer.