Elucidating pharmacodynamic interaction of silver nanoparticle - topical deliverable antibiotics

• Published in: Scientific reports Vol. 6; no. 1; p. 29982
• Main Authors: Thirumurugan, G, Seshagiri Rao, J V L N, Dhanaraju, M D
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 18.07.2016
• Subjects: Administration, Topical; Anti-Bacterial Agents - administration & dosage; Anti-Bacterial Agents - pharmacology; Antibiotics; Antimicrobial agents; Bacterial infections; Biofilms - drug effects; Drugs; E coli; Electrophoresis, Polyacrylamide Gel; Escherichia coli - drug effects; Escherichia coli - physiology; Metal Nanoparticles - administration & dosage; Microbial Sensitivity Tests; Microbial Viability - drug effects; Nanoparticles; Pharmaceutical sciences; Pharmacodynamics; Potassium - metabolism; Pseudomonas aeruginosa - drug effects; Pseudomonas aeruginosa - physiology; Reactive Oxygen Species - metabolism; Silver; Silver - administration & dosage; Silver - pharmacology; Staphylococcus aureus - drug effects; Staphylococcus aureus - physiology; Wound healing; India
• DOI: 10.1038/srep29982
• ISSN: 2045-2322

In order to exploit the potential benefits of antimicrobial combination therapy, we need a better understanding of the circumstances under which pharmacodynamic interactions expected. In this study, Pharmacodynamic interactions between silver nanoparticle (SNP) and topical antibiotics such as Cefazolin (CEF), Mupirocin (MUP), Gentamycin (GEN), Neomycin (NEO), Tetracycline (TET), Vancomycin (VAN) were investigated using the MIC test, Combination assay followed by Fractional Inhibitory concentration Index and Agar well diffusion method. SNP + MUP, SNP + NEO, SNP + VAN combinations showed Synergism (SN) and SNP + CEF, SNP + GEN, SNP + TET showed Partial synergism (PS) against Staphylococcus aureus. Four combinations (SNP + CEF, SNP + MUP, SNP + GEN, SNP + VAN) showed SN, SNP + TET showed PS and Indifferent effect (ID) were observed for SNP + NEO against Pseudomonas aeruginosa. SN was observed for SNP + CEF, SNP + GEN, SNP + NEO, SNP + TET and SNP + MUP showed ID, SNP + VAN showed PS against Escherichia coli. In addition, we elucidated the possible mechanism involved in the pharmacodynamic interaction between SNP-topical antibiotics by increased ROS level, membrane damage following protein release, K(+) leakage and biofilm inhibition. Thus, our findings support that conjugation of the SNP with topical antibiotics have great potential in the topical formulation when treating complex resistant bacterial infections and where there is a need of more concentration to kill pathogenic bacteria.