Synthesis and characterization of silver nanoparticles as a potential sensor for volatile organosulfides for visual detection of postharvest storage in garlic

Abstract

Abstract Garlic, one of the most popular spices used in manufacturing many food products, is subjected to fungal and bacterial diseases resulting to substantial losses in quantity and quality. Specific detection tools for garlic spoilage will be an asset in relieving these losses during postharvest storage. In this study, stable yellow-colored silver nanoparticle colloidal solution was studied as a potential sensor for volatile organosulfides in garlic. The silver nanoparticles (AgNPs) were synthesized by chemical reduction method where silver nitrate was taken as metal precursor, sodium borohydride as reducing agent, and polyethylene glycol as stabilizing agent. The silver nanoparticles were characterized by UV-Vis Spectroscopy and Dynamic Light Scattering (DLS). The spectral analysis revealed the formation of silver nanoparticles by exhibiting the typical surface plasmon absorption peak at around 395 nm. The DLS results show two populations of AgNPs with particle sizes of 3 nm and 50 nm. The volume ratio of sodium sulfite to be added in the silver nanoparticle and the reaction time was also determined. Synthesized AgNPs could detect sodium sulfite at 0.52 to 50 µM concentration range. This simple method indicated the potential of silver nanoparticles as a powerful detection tool for volatile organosulfides in garlic.