Size-controlled silver nanoparticles synthesized over the range 5–100 nm using the same protocol and their antibacterial efficacy

By S. Agnihotri, S. Mukherji, S. Mukherji. 2014

1,558 citations recorded by the source corpus.

A systematic and detailed study for size-specific antibacterial efficacy of silver nanoparticles (AgNPs) synthesized using a co-reduction approach is presented here. Nucleation and growth kinetics during the synthesis process was precisely controlled and AgNPs of average size 5, 7, 10, 15, 20, 30, 50, 63, 85, and 100 nm were synthesized with good yield and monodispersity. We found the bacteriostatic/bactericidal effect of AgNPs to be size and dose-dependent as determined by the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of silver nanoparticles against four bacterial strains. Out of the tested strains, Escherichia coli MTCC 443 and Staphylococcus aureus NCIM 5201 were found to be the most and least sensitive strains regardless of AgNP size. For AgNPs with less than 10 nm size, the antibacterial efficacy was significantly enhanced as revealed through delayed bacterial growth kinetics, corresponding MIC/MBC values and disk diffusion tests. AgNPs of the smallest size, i.e., 5 nm demonstrated the best results and mediated the fastest bactericidal activity against all the tested strains compared to AgNPs having 7 nm and 10 nm sizes at similar bacterial concentrations. TEM analysis of AgNP treated bacterial cells showed the presence of AgNPs on the cell membrane, and AgNPs internalized within the cells.

Subfields: Materials Chemistry, Pollution

View Paper: https://www.semanticscholar.org/paper/93e069b08ea9bf0abae4b1f59b1c38c4cf11a109

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In Materials Chemistry

1. Sang Hun Lee
2. K. S. Siddiqi
3. Bong-Hyun Jun
4. R. Rao
5. C. Liao
6. S. Tjong
7. Azamal Husen
8. Yuchao Li

In Pollution

1. C. Liao
2. S. Tjong
3. Yuchao Li

Citations in the corpus

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• Size- and Shape-Dependent Antibacterial Studies of Silver Nanoparticles Synthesized by Wet Chemical Routes (2016, methodology): “These ions may affect the bacterial DNA replication functions; deactivating the production of some enzymes and cellular proteins necessary for adenosine tri-phosphate (ATP) synthesis [2,15].”
• Silver Nanoparticles and Their Antibacterial Applications (2021, background): “Then the bactericidal and bacteriostatic capacity of nanoparticles between 5 to 100 nm were evaluated against Gram-negative and Grampositive bacteria [44].”