Effect of visible light onto self-assembly in l-cysteine-silver solution.

Effects of irradiation with visible light on the process of self-assembly in an aqueous l-cysteine-silver solution (CSS) and hydrogels based on were investigated using a set of physico-chemical methods. It was found that the exposure to light of CSS and hydrogels based on l-cysteine and silver acetate colors them firstly into yellow and subsequently to brown, which is due to the plasmon resonance of free electrons at the surface of resulting silver nanoparticles (AgNPs). A mechanism involving participation of AgNPs was proposed for the self-assembly in CSS and hydrogel.