This document is written work internship research was to study the effect of the concentration of peptone culture media in the antimicrobial activity of silver nanoparticles on bacterial Escherichia coli strain DH5a . This project comes thanks to the wide range of applications of silver nanoparticles as an option to control and prevent infectious diseases and the need to know the effects and interactions of nanomaterials with biological systems . It was found that the antimicrobial effect of AGNPS , evaluated by the analysis of the minimum inhibitory concentrations is directly related to the amount of peptone culture medium.