Saliva and light as templates for the green synthesis of silver nanoparticles

We report a method for the synthesis of silver nanoparticles using an aqueous saliva solution and irradiation with light from a mercury metal halide lamp. Bi-deionized water was used as the solvent, and surfactants or reducing agents were substituted by saliva and light in the procedure, characterizing the process as a “green” synthesis. The light was used to reduce silver ions (Ag+) to metallic silver (Ag0). The average size, size distribution, and morphology of the nanoparticles were determined by transmission electron microscopy (TEM), UV/visible absorption spectrophotometry and Fourier transform infrared spectroscopy (FTIR). Spherical nanoparticles of ∼20 nm in size were present after the lamp illumination. This methodology represents a non-invasive approach for disease detection and possesses a good potential for diagnostics applications.