Supercritical assisted electrospray is an emerging process used for the production of polymeric micro- and nanoparticles of controlled size and distribution. The main innovation consists of the addition of supercritical CO2 to the polymeric solution, with the aim of obtaining an expanded liquid, characterized by reduced viscosity and surface tension. Cellulose acetate (CA) was selected as the model polymer, thanks to its peculiarities, such as low cost, biodegradability and biocompatibility. The experiments were performed at different pressures (from 80 bar to 140 bar) and polymer concentrations (from 0.2% to 1% w/w). CA nanoparticles were successfully produced; working at 140 bar and 30 kV, particles characterized by a mean diameter in the range from 266.7±145 nm to 343.9±120 nm were obtained, processing 0.2% w/w and 1% w/w CA solutions, respectively. These results open the way to the production of biopolymeric sub-microcarriers that, loaded with active molecules, can be used in nutraceuticals.