Effects of Caramelization Products on Synthesis of Silver Nanoparticles by Using Silver-Containing Glass Powder and Various Reducing Sugars in an Aqueous System

Abstract

Silver-containing glass powder can be used as a sustainable source of silver ions in inhomogeneous synthetic systems of strictly size-controlled silver nanoparticles using an aqueous solution of reducing sugars. The caramelization products derived from sugars in this synthetic system contained promoters of silver ion release from silver-containing glass powder and suppressers of nanoparticle growth. In this study, the effects of caramelization products on the size control of nanoparticles were investigated using four types of reducing sugars: glucose, fructose, maltose, and lactose. It was found that acidic components of caramelization products were corresponding to promoters of silver ion release. The acidity of the product suspensions increased with increasing initial concentrations of each sugar. For monosaccharides, glucose and fructose, nanoparticle sizes significantly increased (3.5–50 nm) with the acidity of the product suspensions. In contrast, for disaccharides, maltose and lactose, the nanoparticle sizes slightly increased (4.1–7.1 nm) with acidity. This difference arose from a balance of the effects of both silver ion release promoters and nanoparticle growth suppressers: the monosaccharide systems were dominated by the effect of silver ion release promoters to promote particle growth, whereas the disaccharide systems were regulated by the relationship between the effects of both components.