The impression of amphiphilic polymers on stability of silver nanoparticles produced by aqueous extract of dried Juglans regia green husk

The high surface to volume ratio of nanoparticles results in high reactivity which leads to particle aggregation. However, protection of the particles by a capping agent provides colloidal stability. Stabilizers are usually used to obtain well-dispersed nanoparticles and protect them from agglomeration. This stabilization is achieved due to the reactions between functional groups. Colloidal stability is a function of many factors including the type of capping agents and the environmental conditions, such as pH and ionic strength. Nanoparticles are stabilized electrostatically, sterically, and electrosterically. In this study, the green synthesis of silver nanoparticles (AgNPs) using aqueous extract of dried Juglans Regia green husk was done in the presence of several materials including SDS, Alginate as well as (lactic acid)n-(ethylene glycol)m-(lactic acid)n (LAn-EGm-LAn) triblock biodegradable polymers at room temperature. Nanoparticle stability was examined through the visible absorption spectrum. Results show that the sharp and symmetric absorption peak of the AgNps has a significant blue-shift in LA15-EG68-LA15 block polymer solution. This indicates a good stability of the nanoparticles. Therefore, LA15-EG68-LA15 polymer was chosen as the most suitable capping agent.

Keywords:

silver nanoparticle , stabilizer , aggregation , capping agent , nanobiotechnology