Antibacterial Activity of Silver Nanoparticles Against Gram-Positive and Gram-Negative Bacteria|
Posted by Admin on Monday, July, 04 2011 and filed under Research
Key topics: Silver Nanoparticles
Pontificia Universidad Catolica del Peru, Engineering Department, Lima, Peru.
Synthesis of nanosized particles with antibacterial properties is of great interest in the development of new pharmaceutical products. Silver nanoparticles (AgNPs) are known to have inhibitory and bactericidal effects. In this article we present the synthesis of AgNPs prepared by chemical reduction from aqueous solutions of silver nitrate, containing a mixture of hydrazine hydrate and sodium citrate as reductants and sodium dodecyl sulfate as a stabilizer. The results of the characterization of the AgNPs show agglomerates of grains with a narrow size distribution (from 40 to 60 nm), whereas the radii of the individual particles are between 10 and 20 nm. Finally, the antibacterial activity was measured by the Kirby-Bauer method. The results showed reasonable bactericidal activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The standard dilution micromethod, determining the minimum inhibitory concentration leading to inhibition of bacterial growth, is still under way. Preliminary results have been obtained.