Effect of polyethyleneimine stabilizer on size and morphology of gold nanoparticles

Abstract

Background: Gold nanoparticles have attracted much more attention in many applications and the kind of these applications depends on the size and morphology of gold nanoparticles. Many polymers were used to control the size and shape of gold nanoparticles. Methodology: Herein, gold nanoparticles were prepared at room temperature by reducing tetrachloroauric (III) acid using gallic acid as a reducing agent in the presence of polyethyleneimine as a stabilizer. The role and the effect of the amount added from polyethyleneimine (PEI) on the size and morphology of the prepared gold nanoparticles were studied. The colloidal gold nanoparticles solutions were characterized using UV-vis spectrophotometer, transmission electron microscopy and fourier transform infra-red spectroscopy. Results: The prepared gold nanoparticles were found to be uniform circular particles with size range 5-12 nm. The UV-vis spectrophotometer revealed that in the absence of polyethyleneimine no gold nanoparticles were developed, this clarifies that polyethyleneimine is not only acted as a stabilizer but also as a reducing agent. Conclusion: The particle size of the prepared gold nanoparticles was found to be decreased as the amount of polyethyleneimine increase.