Research Article published by International Research Journal of Pure &
Applied Chemistry
The purpose of this work was to study the effect of various process and formulation parameters on
size and shapes of silver nanoparticles (AgNPs) based on surface plasmon resonance (SPR).
AgNPs were prepared by chemical reduction using formaldehyde (HCHO) as reducing agent and
capped by polyethylene glycol (PEG). Effect of several processing variables including the
concentration and volume of capping agent and reaction time is reported. The size of
monodispersed nanoparticles was between 30-100 nm and was stable for three months at both
room temperature and 4°C.