Significant arsenic (As) contents have been reported in rice. The most toxic As species, inorganic arsenic (iAs), is one of the most common species in rice. Thus, it is important monitor iAs in this matrix. In this work, plasmonic silver nanoparticles were functionalized with polyethylene glycol (Ag@PEG) and used as a sensor platform for iAs quantification in rice by spectrophotometry. The proposed method showed good linearity in a range between 1 and 15 μg kg