Nano polyamidoamine-G7 dendrimer synthesis and assessment the antibacterial effect in vitro

Background: Nano scale dendrimers are macromolecules synthetic which frequently used in medical and health field. Because traditional antibiotics inevitably induce bacterial resistance, which is responsible for many treatment failures, there is an urgent need to develop novel antibiotic drugs. This study was aimed to examine Synthesis and the anti-bacterial effect of NanoPolyamidoamine-G7 (NPAMAM-G7) dendrimer on Escherichia Coli, Proteus Mirabilis, Salmonella Typhi, Bacillus Subtilis and Staphylococcus Aureus. Methods: In this experimental study that has been conducted in June 2015 in the Laboratory of Microbiology, Iran University of Medical Science, NPAMAM-G7 dendrimers was synthesized by Tomaliaâ��s divergent growth approach. The antibacterial effects of NPA-MAM-G7 dendrimer were studied by disc diffusion and micro-dilution method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against gram-positive and gram-negative bacteria were determined according to Clinical and Laboratory Standards Institute (CLSI) guideline. Standard discs were prepared using different concentrations of dendrimer on Mueller-Hinton agar plates. Results: Zone of inhibition in concentration 25 I¼g/ml of NPAMAM-G7 dendrimers for Escherichia Coli, Proteus Mirabilis, Salmonella Typhi, Bacillus Subtilis and Staphylococcus Aureus were 26, 38, 36, 22 and 25 mm, respectively. Regarding the zone of inhibition in gram negative bacteria with gram positive ones was P= 0.16 and was not significant difference. The MIC for Salmonella Typhi was 0.025, for Proteus Mirabilis, Bacillus Subtilis, Staphylococcus Aureus and Escherichia Coli was 0.25 I¼g/ml. The MBC for Salmonella Typhi was 25I¼g/ml, for Proteus Mirabilis and Bacillus Subtilis was 50 I¼g/ml and for Escherichia Coli and Staphylococcus Aureus was 100 I¼g/ml. The least of sensitivity against NPAMAM-G7 related to Escherichia Coli and Staphylococcus Aureus and the most of sensitivity related to Salmonella Typhi. Conclusion: The NPAMAM-G7 dendrimer with end amine groups exhibited a positive impact on the removal of standard strains, gram-positive and gram-negative bacteria. Therefore, it is possible to use these nanodendrimers as antibacterial in the future. © 2016, Tehran University of Medical Sciences. All rights reserved.