The presented study concerns the preparation and investigation of silver particles in presence of hydroxylated polyester dendrimers used as stabilizing agent. Altogether a full series of water soluble and aliphatic bis-MPA dendrimers from first to fifth generation was used as to stabilize silver nanoparticles in situ. A special focus is set on the biological properties. The antibacterial properties of the dendrimer stabilized silver particles are tested against Escherichia coli and the toxicity against human cells is tested with the human epithelial cell line A549. Under the chosen testing arrangement, it was observed that the silver particles contain a significant antibacterial effect against E. coli. Silver particles stabilized in situ with dendrimers of higher generation seem to contain a stronger antibacterial property. No toxicity against human cells was observed for the silver particles even in case of the highest investigated silver concentration. Altogether the here prepared and investigated silver particles could offer a great potential for application as antibacterial agent with low human toxicity.