Common materials used in nanoprecipitation include biodegradable polymers such as polylactic acid (PLA), poly(lactic-co-glycolic acid) (PLGA), and polycaprolactone (PCL). These materials are chosen for their biocompatibility and ability to degrade into non-toxic byproducts. The choice of solvent and stabilizer also plays a critical role in determining the final properties of the nanoparticles.